BASELINE: Update Chromium to 85.0.4183.14085-based

Change-Id: Iaa42f4680837c57725b1344f108c0196741f6057
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

8 files changed, 353 insertions, 138 deletions

diff --git a/chromium/testing/scripts/OWNERS b/chromium/testing/scripts/OWNERS
index bccebb03dfb..5fe2f0fa096 100644
--- a/chromium/testing/scripts/OWNERS
+++ b/chromium/testing/scripts/OWNERS
@@ -2,14 +2,18 @@
 # and understand the implications of changing these files.
 
 dpranke@chromium.org
+dpranke@google.com
 kbr@chromium.org
 martiniss@chromium.org
 
 per-file check_static_initializers.py=thakis@chromium.org
 per-file check_static_initializers.py=thomasanderson@chromium.org
 
-per-file run-wpt_tests.py=lpz@chromium.org
+per-file run_wpt_tests.py=lpz@chromium.org
 per-file run_wpt_tests.py=robertma@chromium.org
+per-file wpt_common.py=lpz@chromium.org
+per-file wpt_common.py=robertma@chromium.org
+per-file wpt_common.py=rmhasan@chromium.org
 
 per-file run_performance_tests.py=johnchen@chromium.org
 per-file run_performance_tests.py=wenbinzhang@google.com
diff --git a/chromium/testing/scripts/get_compile_targets.py b/chromium/testing/scripts/get_compile_targets.py
index aed1c569e8a..1e5fcf02a96 100755
--- a/chromium/testing/scripts/get_compile_targets.py
+++ b/chromium/testing/scripts/get_compile_targets.py
@@ -30,7 +30,8 @@ def main(argv):
     if filename in ('common.py',
                     'get_compile_targets.py',
                     'gpu_integration_test_adapter.py',
-                    'sizes_common.py'):
+                    'sizes_common.py',
+                    'wpt_common.py'):
       continue
 
     with common.temporary_file() as tempfile_path:
diff --git a/chromium/testing/scripts/representative_perf_test_data/representatives_frame_times_upper_limit.json b/chromium/testing/scripts/representative_perf_test_data/representatives_frame_times_upper_limit.json
index 5b370b87b67..8f6d3038f14 100644
--- a/chromium/testing/scripts/representative_perf_test_data/representatives_frame_times_upper_limit.json
+++ b/chromium/testing/scripts/representative_perf_test_data/representatives_frame_times_upper_limit.json
@@ -6,7 +6,9 @@
     },
     "filter_terrain_svg": {
       "ci_095": 0.377,
-      "avg": 31.486
+      "avg": 31.486,
+      "experimental": true,
+      "_comment": "crbug.com/1053614"
     },
     "web_animation_value_type_transform_complex": {
       "ci_095": 1.783,
@@ -55,7 +57,9 @@
     },
     "css_value_type_shadow": {
       "ci_095": 1.284,
-      "avg": 49.386
+      "avg": 49.386,
+      "experimental": true,
+      "_comment": "crbug.com/1093313"
     },
     "nvidia_vertex_buffer_object": {
       "ci_095": 3.37,
@@ -85,7 +89,9 @@
     },
     "css_value_type_shadow": {
       "ci_095": 13.611,
-      "avg": 61.261
+      "avg": 61.261,
+      "experimental": true,
+      "_comment": "crbug.com/1093313"
     },
     "animometer_webgl_attrib_arrays": {
       "ci_095": 0.495,
diff --git a/chromium/testing/scripts/run_android_wpt.py b/chromium/testing/scripts/run_android_wpt.py
index e657f092f2d..7950d391f79 100755
--- a/chromium/testing/scripts/run_android_wpt.py
+++ b/chromium/testing/scripts/run_android_wpt.py
@@ -33,6 +33,7 @@ import shutil
 import sys
 
 import common
+import wpt_common
 
 logger = logging.getLogger(__name__)
 
@@ -40,37 +41,35 @@ SRC_DIR = os.path.abspath(
     os.path.join(os.path.dirname(__file__), os.pardir, os.pardir))
 
 BUILD_ANDROID = os.path.join(SRC_DIR, 'build', 'android')
+BLINK_TOOLS_DIR = os.path.join(
+    SRC_DIR, 'third_party', 'blink', 'tools')
+CATAPULT_DIR = os.path.join(SRC_DIR, 'third_party', 'catapult')
+DEFAULT_WPT = os.path.join(wpt_common.WEB_TESTS_DIR, 'external', 'wpt', 'wpt')
+PYUTILS = os.path.join(CATAPULT_DIR, 'common', 'py_utils')
+
+if PYUTILS not in sys.path:
+  sys.path.append(PYUTILS)
+
+if BLINK_TOOLS_DIR not in sys.path:
+  sys.path.append(BLINK_TOOLS_DIR)
 
 if BUILD_ANDROID not in sys.path:
   sys.path.append(BUILD_ANDROID)
 
 import devil_chromium
 
+from blinkpy.web_tests.port.android import (
+    PRODUCTS, PRODUCTS_TO_EXPECTATION_FILE_PATHS, ANDROID_WEBLAYER,
+    ANDROID_WEBVIEW, CHROME_ANDROID, ANDROID_DISABLED_TESTS)
+
 from devil import devil_env
 from devil.android import apk_helper
 from devil.android import device_utils
 from devil.android.tools import system_app
 from devil.android.tools import webview_app
 
-CATAPULT_DIR = os.path.join(SRC_DIR, 'third_party', 'catapult')
-PYUTILS = os.path.join(CATAPULT_DIR, 'common', 'py_utils')
-
-if PYUTILS not in sys.path:
-  sys.path.append(PYUTILS)
-
 from py_utils.tempfile_ext import NamedTemporaryDirectory
 
-BLINK_TOOLS_DIR = os.path.join(SRC_DIR, 'third_party', 'blink', 'tools')
-WEB_TESTS_DIR = os.path.join(BLINK_TOOLS_DIR, os.pardir, 'web_tests')
-DEFAULT_WPT = os.path.join(WEB_TESTS_DIR, 'external', 'wpt', 'wpt')
-
-ANDROID_WEBLAYER = 'android_weblayer'
-ANDROID_WEBVIEW = 'android_webview'
-CHROME_ANDROID = 'chrome_android'
-
-# List of supported products.
-PRODUCTS = [ANDROID_WEBLAYER, ANDROID_WEBVIEW, CHROME_ANDROID]
-
 
 class PassThroughArgs(argparse.Action):
   pass_through_args = []
@@ -107,28 +106,18 @@ def _get_adapter(device):
     return WPTClankAdapter(device)
 
 
-class WPTAndroidAdapter(common.BaseIsolatedScriptArgsAdapter):
+class WPTAndroidAdapter(wpt_common.BaseWptScriptAdapter):
 
   def __init__(self, device):
     self.pass_through_wpt_args = []
     self.pass_through_binary_args = []
     self._metadata_dir = None
-    self._test_apk = None
-    self._missing_test_apk_arg = None
     self._device = device
     super(WPTAndroidAdapter, self).__init__()
     # Arguments from add_extra_argumentsparse were added so
     # its safe to parse the arguments and set self._options
     self.parse_args()
 
-  def generate_test_output_args(self, output):
-    return ['--log-chromium', output]
-
-  def generate_sharding_args(self, total_shards, shard_index):
-    return ['--total-chunks=%d' % total_shards,
-        # shard_index is 0-based but WPT's this-chunk to be 1-based
-        '--this-chunk=%d' % (shard_index + 1)]
-
   @property
   def rest_args(self):
     rest_args = super(WPTAndroidAdapter, self).rest_args
@@ -169,29 +158,25 @@ class WPTAndroidAdapter(common.BaseIsolatedScriptArgsAdapter):
     raise NotImplementedError
 
   def _maybe_build_metadata(self):
-    if not self._test_apk:
-      assert self._missing_test_apk_arg, (
-          'self._missing_test_apk_arg was not set.')
-      logger.warning('%s was not set, skipping metadata generation.' %
-                     self._missing_test_apk_arg)
-      return
-
     metadata_builder_cmd = [
          sys.executable,
-         os.path.join(BLINK_TOOLS_DIR, 'build_wpt_metadata.py'),
-         '--android-apk',
-         self._test_apk,
+         os.path.join(wpt_common.BLINK_TOOLS_DIR, 'build_wpt_metadata.py'),
+         '--android-product',
+         self.options.product,
+         '--ignore-default-expectations',
          '--metadata-output-dir',
          self._metadata_dir,
          '--additional-expectations',
-         os.path.join(WEB_TESTS_DIR, 'android', 'AndroidWPTNeverFixTests')
+         ANDROID_DISABLED_TESTS,
     ]
     metadata_builder_cmd.extend(self._extra_metadata_builder_args())
-    common.run_command(metadata_builder_cmd)
+    return common.run_command(metadata_builder_cmd)
 
   def run_test(self):
     with NamedTemporaryDirectory() as self._metadata_dir, self._install_apks():
-      self._maybe_build_metadata()
+      metadata_command_ret = self._maybe_build_metadata()
+      if metadata_command_ret != 0:
+          return metadata_command_ret
       return super(WPTAndroidAdapter, self).run_test()
 
   def _install_apks(self):
@@ -202,24 +187,6 @@ class WPTAndroidAdapter(common.BaseIsolatedScriptArgsAdapter):
     # which was deleted
     self._metadata_dir = None
 
-  def do_post_test_run_tasks(self):
-    # Move json results into layout-test-results directory
-    results_dir = os.path.dirname(self.options.isolated_script_test_output)
-    layout_test_results = os.path.join(results_dir, 'layout-test-results')
-    os.mkdir(layout_test_results)
-    shutil.copyfile(self.options.isolated_script_test_output,
-                    os.path.join(layout_test_results, 'full_results.json'))
-    # create full_results_jsonp.js file which is used to
-    # load results into the results viewer
-    with open(self.options.isolated_script_test_output, 'r') as full_results, \
-         open(os.path.join(
-             layout_test_results, 'full_results_jsonp.js'), 'w') as json_js:
-      json_js.write('ADD_FULL_RESULTS(%s);' % full_results.read())
-    # copy layout test results viewer to layout-test-results directory
-    shutil.copyfile(
-        os.path.join(WEB_TESTS_DIR, 'fast', 'harness', 'results.html'),
-        os.path.join(layout_test_results, 'results.html'))
-
   def add_extra_arguments(self, parser):
     # TODO: |pass_through_args| are broke and need to be supplied by way of
     # --binary-arg".
@@ -282,11 +249,6 @@ class WPTWeblayerAdapter(WPTAndroidAdapter):
   WEBLAYER_SHELL_PKG = 'org.chromium.weblayer.shell'
   WEBLAYER_SUPPORT_PKG = 'org.chromium.weblayer.support'
 
-  def __init__(self, device):
-    super(WPTWeblayerAdapter, self).__init__(device)
-    self._test_apk = self.options.weblayer_shell
-    self._missing_test_apk_arg = '--weblayer-shell'
-
   @contextlib.contextmanager
   def _install_apks(self):
     install_weblayer_shell_as_needed = maybe_install_user_apk(
@@ -304,8 +266,7 @@ class WPTWeblayerAdapter(WPTAndroidAdapter):
   def _extra_metadata_builder_args(self):
     return [
       '--additional-expectations',
-      os.path.join(WEB_TESTS_DIR,
-                   'android', 'WeblayerWPTOverrideExpectations')]
+      PRODUCTS_TO_EXPECTATION_FILE_PATHS[ANDROID_WEBLAYER]]
 
   def add_extra_arguments(self, parser):
     super(WPTWeblayerAdapter, self).add_extra_arguments(parser)
@@ -327,11 +288,6 @@ class WPTWebviewAdapter(WPTAndroidAdapter):
 
   SYSTEM_WEBVIEW_SHELL_PKG = 'org.chromium.webview_shell'
 
-  def __init__(self, device):
-    super(WPTWebviewAdapter, self).__init__(device)
-    self._test_apk = self.options.system_webview_shell
-    self._missing_test_apk_arg = '--system-webview-shell'
-
   @contextlib.contextmanager
   def _install_apks(self):
     install_shell_as_needed = maybe_install_user_apk(
@@ -346,8 +302,7 @@ class WPTWebviewAdapter(WPTAndroidAdapter):
   def _extra_metadata_builder_args(self):
     return [
       '--additional-expectations',
-      os.path.join(
-          WEB_TESTS_DIR, 'android', 'WebviewWPTOverrideExpectations')]
+      PRODUCTS_TO_EXPECTATION_FILE_PATHS[ANDROID_WEBVIEW]]
 
   def add_extra_arguments(self, parser):
     super(WPTWebviewAdapter, self).add_extra_arguments(parser)
@@ -366,11 +321,6 @@ class WPTWebviewAdapter(WPTAndroidAdapter):
 
 class WPTClankAdapter(WPTAndroidAdapter):
 
-  def __init__(self, device):
-    super(WPTClankAdapter, self).__init__(device)
-    self._test_apk = self.options.chrome_apk
-    self._missing_test_apk_arg = '--chrome-apk'
-
   @contextlib.contextmanager
   def _install_apks(self):
     install_clank_as_needed = maybe_install_user_apk(
@@ -381,7 +331,7 @@ class WPTClankAdapter(WPTAndroidAdapter):
   def _extra_metadata_builder_args(self):
     return [
       '--additional-expectations',
-      os.path.join(WEB_TESTS_DIR, 'android', 'ClankWPTOverrideExpectations')]
+      PRODUCTS_TO_EXPECTATION_FILE_PATHS[CHROME_ANDROID]]
 
   def add_extra_arguments(self, parser):
     super(WPTClankAdapter, self).add_extra_arguments(parser)
diff --git a/chromium/testing/scripts/run_android_wpt.pydeps b/chromium/testing/scripts/run_android_wpt.pydeps
index 3f75fc0f319..06416555afa 100644
--- a/chromium/testing/scripts/run_android_wpt.pydeps
+++ b/chromium/testing/scripts/run_android_wpt.pydeps
@@ -6,8 +6,66 @@
 //build/android/pylib/constants/host_paths.py
 //testing/scripts/common.py
 //testing/scripts/run_android_wpt.py
+//testing/scripts/wpt_common.py
 //testing/test_env.py
 //testing/xvfb.py
+//third_party/blink/tools/blinkpy/__init__.py
+//third_party/blink/tools/blinkpy/common/__init__.py
+//third_party/blink/tools/blinkpy/common/checkout/__init__.py
+//third_party/blink/tools/blinkpy/common/checkout/git.py
+//third_party/blink/tools/blinkpy/common/exit_codes.py
+//third_party/blink/tools/blinkpy/common/find_files.py
+//third_party/blink/tools/blinkpy/common/host.py
+//third_party/blink/tools/blinkpy/common/html_diff.py
+//third_party/blink/tools/blinkpy/common/memoized.py
+//third_party/blink/tools/blinkpy/common/net/__init__.py
+//third_party/blink/tools/blinkpy/common/net/network_transaction.py
+//third_party/blink/tools/blinkpy/common/net/results_fetcher.py
+//third_party/blink/tools/blinkpy/common/net/web.py
+//third_party/blink/tools/blinkpy/common/net/web_test_results.py
+//third_party/blink/tools/blinkpy/common/path_finder.py
+//third_party/blink/tools/blinkpy/common/read_checksum_from_png.py
+//third_party/blink/tools/blinkpy/common/system/__init__.py
+//third_party/blink/tools/blinkpy/common/system/executive.py
+//third_party/blink/tools/blinkpy/common/system/filesystem.py
+//third_party/blink/tools/blinkpy/common/system/path.py
+//third_party/blink/tools/blinkpy/common/system/platform_info.py
+//third_party/blink/tools/blinkpy/common/system/profiler.py
+//third_party/blink/tools/blinkpy/common/system/system_host.py
+//third_party/blink/tools/blinkpy/common/system/user.py
+//third_party/blink/tools/blinkpy/common/unified_diff.py
+//third_party/blink/tools/blinkpy/w3c/__init__.py
+//third_party/blink/tools/blinkpy/w3c/wpt_manifest.py
+//third_party/blink/tools/blinkpy/web_tests/__init__.py
+//third_party/blink/tools/blinkpy/web_tests/breakpad/__init__.py
+//third_party/blink/tools/blinkpy/web_tests/breakpad/dump_reader.py
+//third_party/blink/tools/blinkpy/web_tests/breakpad/dump_reader_multipart.py
+//third_party/blink/tools/blinkpy/web_tests/breakpad/dump_reader_win.py
+//third_party/blink/tools/blinkpy/web_tests/builder_list.py
+//third_party/blink/tools/blinkpy/web_tests/controllers/__init__.py
+//third_party/blink/tools/blinkpy/web_tests/controllers/repaint_overlay.py
+//third_party/blink/tools/blinkpy/web_tests/layout_package/__init__.py
+//third_party/blink/tools/blinkpy/web_tests/layout_package/bot_test_expectations.py
+//third_party/blink/tools/blinkpy/web_tests/layout_package/json_results_generator.py
+//third_party/blink/tools/blinkpy/web_tests/models/__init__.py
+//third_party/blink/tools/blinkpy/web_tests/models/test_configuration.py
+//third_party/blink/tools/blinkpy/web_tests/models/test_expectations.py
+//third_party/blink/tools/blinkpy/web_tests/models/test_failures.py
+//third_party/blink/tools/blinkpy/web_tests/models/test_run_results.py
+//third_party/blink/tools/blinkpy/web_tests/models/typ_types.py
+//third_party/blink/tools/blinkpy/web_tests/port/__init__.py
+//third_party/blink/tools/blinkpy/web_tests/port/android.py
+//third_party/blink/tools/blinkpy/web_tests/port/base.py
+//third_party/blink/tools/blinkpy/web_tests/port/driver.py
+//third_party/blink/tools/blinkpy/web_tests/port/factory.py
+//third_party/blink/tools/blinkpy/web_tests/port/linux.py
+//third_party/blink/tools/blinkpy/web_tests/port/server_process.py
+//third_party/blink/tools/blinkpy/web_tests/port/win.py
+//third_party/blink/tools/blinkpy/web_tests/servers/__init__.py
+//third_party/blink/tools/blinkpy/web_tests/servers/apache_http.py
+//third_party/blink/tools/blinkpy/web_tests/servers/pywebsocket.py
+//third_party/blink/tools/blinkpy/web_tests/servers/server_base.py
+//third_party/blink/tools/blinkpy/web_tests/servers/wptserve.py
 //third_party/catapult/common/py_utils/py_utils/__init__.py
 //third_party/catapult/common/py_utils/py_utils/cloud_storage.py
 //third_party/catapult/common/py_utils/py_utils/cloud_storage_global_lock.py
@@ -30,7 +88,7 @@
 //third_party/catapult/devil/devil/android/constants/chrome.py
 //third_party/catapult/devil/devil/android/constants/file_system.py
 //third_party/catapult/devil/devil/android/decorators.py
-//third_party/catapult/devil/devil/android/device_blacklist.py
+//third_party/catapult/devil/devil/android/device_denylist.py
 //third_party/catapult/devil/devil/android/device_errors.py
 //third_party/catapult/devil/devil/android/device_signal.py
 //third_party/catapult/devil/devil/android/device_temp_file.py
@@ -71,4 +129,19 @@
 //third_party/catapult/devil/devil/utils/timeout_retry.py
 //third_party/catapult/devil/devil/utils/watchdog_timer.py
 //third_party/catapult/devil/devil/utils/zip_utils.py
+//third_party/catapult/third_party/typ/typ/__init__.py
+//third_party/catapult/third_party/typ/typ/arg_parser.py
+//third_party/catapult/third_party/typ/typ/artifacts.py
+//third_party/catapult/third_party/typ/typ/expectations_parser.py
+//third_party/catapult/third_party/typ/typ/fakes/__init__.py
+//third_party/catapult/third_party/typ/typ/fakes/host_fake.py
+//third_party/catapult/third_party/typ/typ/host.py
+//third_party/catapult/third_party/typ/typ/json_results.py
+//third_party/catapult/third_party/typ/typ/pool.py
+//third_party/catapult/third_party/typ/typ/printer.py
+//third_party/catapult/third_party/typ/typ/python_2_3_compat.py
+//third_party/catapult/third_party/typ/typ/runner.py
+//third_party/catapult/third_party/typ/typ/stats.py
+//third_party/catapult/third_party/typ/typ/test_case.py
+//third_party/catapult/third_party/typ/typ/version.py
 //third_party/catapult/third_party/zipfile/zipfile_2_7_13.py
diff --git a/chromium/testing/scripts/run_rendering_benchmark_with_gated_performance.py b/chromium/testing/scripts/run_rendering_benchmark_with_gated_performance.py
index db8852291f1..4c58b74944b 100755
--- a/chromium/testing/scripts/run_rendering_benchmark_with_gated_performance.py
+++ b/chromium/testing/scripts/run_rendering_benchmark_with_gated_performance.py
@@ -124,12 +124,19 @@ class RenderingRepresentativePerfTest(object):
 
     self.benchmark = self.options.benchmarks
     out_dir_path = os.path.dirname(self.options.isolated_script_test_output)
-    self.output_path = os.path.join(
-      out_dir_path, self.benchmark, 'test_results.json')
-    self.results_path = os.path.join(
-      out_dir_path, self.benchmark, 'perf_results.csv')
-
     re_run_output_dir = os.path.join(out_dir_path, 're_run_failures')
+
+    self.output_path = {
+      True: os.path.join(
+        re_run_output_dir, self.benchmark, 'test_results.json'),
+      False: os.path.join(out_dir_path, self.benchmark, 'test_results.json')
+    }
+    self.results_path = {
+      True: os.path.join(
+        re_run_output_dir, self.benchmark, 'perf_results.csv'),
+      False: os.path.join(out_dir_path, self.benchmark, 'perf_results.csv')
+    }
+
     re_run_test_output = os.path.join(re_run_output_dir,
       os.path.basename(self.options.isolated_script_test_output))
     re_run_test_perf_output = os.path.join(re_run_output_dir,
@@ -236,37 +243,38 @@ class RenderingRepresentativePerfTest(object):
           METRIC_NAME, measured_avg, upper_limit_avg))
 
   def interpret_run_benchmark_results(self, rerun=False):
-    with open(self.output_path, 'r+') as resultsFile:
+    with open(self.output_path[rerun], 'r+') as resultsFile:
       initialOut = json.load(resultsFile)
       self.result_recorder[rerun].set_tests(initialOut)
 
-      with open(self.results_path) as csv_file:
+      with open(self.results_path[rerun]) as csv_file:
         csv_obj = csv.DictReader(csv_file)
         values_per_story = self.parse_csv_results(csv_obj)
 
-      # Clearing the result of run_benchmark and write the gated perf results
-      resultsFile.seek(0)
-      resultsFile.truncate(0)
+      if not rerun:
+        # Clearing the result of run_benchmark and write the gated perf results
+        resultsFile.seek(0)
+        resultsFile.truncate(0)
 
     self.compare_values(values_per_story, rerun)
 
-  def run_perf_tests(self, rerun=False):
-    self.return_code |= run_performance_tests.main(
-      self.re_run_args if rerun else self.args)
-    self.interpret_run_benchmark_results(rerun)
+  def run_perf_tests(self):
+    self.return_code |= run_performance_tests.main(self.args)
+    self.interpret_run_benchmark_results(False)
 
-    if not rerun and len(self.result_recorder[rerun].failed_stories) > 0:
+    if len(self.result_recorder[False].failed_stories) > 0:
       # For failed stories we run_tests again to make sure it's not a false
       # positive.
       print('============ Re_run the failed tests ============')
       all_failed_stories = '('+'|'.join(
-        self.result_recorder[rerun].failed_stories)+')'
+        self.result_recorder[False].failed_stories)+')'
       # TODO(crbug.com/1055893): Remove the extra chrome categories after
       # investigation of flakes in representative perf tests.
       self.re_run_args.extend(
         ['--story-filter', all_failed_stories, '--pageset-repeat=3',
          '--extra-chrome-categories=blink,blink_gc,gpu,v8,viz'])
-      self.run_perf_tests(True)
+      self.return_code |= run_performance_tests.main(self.re_run_args)
+      self.interpret_run_benchmark_results(True)
 
       for story_name in self.result_recorder[False].failed_stories.copy():
         if story_name not in self.result_recorder[True].failed_stories:
@@ -283,7 +291,7 @@ class RenderingRepresentativePerfTest(object):
       self.return_code
     ) = self.result_recorder[False].get_output(self.return_code)
 
-    with open(self.output_path, 'r+') as resultsFile:
+    with open(self.output_path[False], 'r+') as resultsFile:
       json.dump(finalOut, resultsFile, indent=4)
     with open(self.options.isolated_script_test_output, 'w') as outputFile:
       json.dump(finalOut, outputFile, indent=4)
diff --git a/chromium/testing/scripts/run_wpt_tests.py b/chromium/testing/scripts/run_wpt_tests.py
index 86ca893abf2..b777ba189b7 100755
--- a/chromium/testing/scripts/run_wpt_tests.py
+++ b/chromium/testing/scripts/run_wpt_tests.py
@@ -16,26 +16,16 @@ Here's the mapping [isolate script flag] : [wpt flag]
 
 import json
 import os
-import shutil
 import sys
 
 import common
+import wpt_common
 
-BLINK_TOOLS_DIR = os.path.join(common.SRC_DIR, 'third_party', 'blink', 'tools')
-WEB_TESTS_DIR = os.path.join(BLINK_TOOLS_DIR, os.pardir, 'web_tests')
 WPT_METADATA_DIR = "../../wpt_expectations_metadata/"
 WPT_OVERRIDE_EXPECTATIONS_PATH = (
     "../../third_party/blink/web_tests/WPTOverrideExpectations")
 
-class WPTTestAdapter(common.BaseIsolatedScriptArgsAdapter):
-
-    def generate_test_output_args(self, output):
-        return ['--log-chromium', output]
-
-    def generate_sharding_args(self, total_shards, shard_index):
-        return ['--total-chunks=%d' % total_shards,
-                # shard_index is 0-based but WPT's this-chunk to be 1-based
-                '--this-chunk=%d' % (shard_index + 1)]
+class WPTTestAdapter(wpt_common.BaseWptScriptAdapter):
 
     @property
     def rest_args(self):
@@ -88,33 +78,11 @@ class WPTTestAdapter(common.BaseIsolatedScriptArgsAdapter):
         ])
         return rest_args
 
-    def do_post_test_run_tasks(self):
-        # Move json results into layout-test-results directory
-        results_dir = os.path.dirname(self.options.isolated_script_test_output)
-        layout_test_results = os.path.join(results_dir, 'layout-test-results')
-        if os.path.exists(layout_test_results):
-            shutil.rmtree(layout_test_results)
-        os.mkdir(layout_test_results)
-        shutil.copyfile(self.options.isolated_script_test_output,
-                        os.path.join(layout_test_results, 'full_results.json'))
-        # create full_results_jsonp.js file which is used to
-        # load results into the results viewer
-        with open(self.options.isolated_script_test_output, 'r') \
-                 as full_results, \
-             open(os.path.join(
-                  layout_test_results, 'full_results_jsonp.js'), 'w') \
-                 as json_js:
-          json_js.write('ADD_FULL_RESULTS(%s);' % full_results.read())
-        # copy layout test results viewer to layout-test-results directory
-        shutil.copyfile(
-            os.path.join(WEB_TESTS_DIR, 'fast', 'harness', 'results.html'),
-            os.path.join(layout_test_results, 'results.html'))
-
 def main():
     # First, generate WPT metadata files.
     common.run_command([
         sys.executable,
-        os.path.join(BLINK_TOOLS_DIR, 'build_wpt_metadata.py'),
+        os.path.join(wpt_common.BLINK_TOOLS_DIR, 'build_wpt_metadata.py'),
         "--metadata-output-dir",
         WPT_METADATA_DIR,
         "--additional-expectations",
diff --git a/chromium/testing/scripts/wpt_common.py b/chromium/testing/scripts/wpt_common.py
new file mode 100644
index 00000000000..ad1ca0eb0db
--- /dev/null
+++ b/chromium/testing/scripts/wpt_common.py
@@ -0,0 +1,205 @@
+# Copyright 2020 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import base64
+import json
+import os
+import shutil
+import sys
+
+import common
+
+BLINK_TOOLS_DIR = os.path.join(common.SRC_DIR, 'third_party', 'blink', 'tools')
+WEB_TESTS_DIR = os.path.join(BLINK_TOOLS_DIR, os.pardir, 'web_tests')
+
+if BLINK_TOOLS_DIR not in sys.path:
+    sys.path.append(BLINK_TOOLS_DIR)
+
+from blinkpy.common.host import Host
+from blinkpy.web_tests.models import test_failures
+
+class BaseWptScriptAdapter(common.BaseIsolatedScriptArgsAdapter):
+    """The base class for script adapters that use wptrunner to execute web
+    platform tests. This contains any code shared between these scripts, such
+    as integrating output with the results viewer. Subclasses contain other
+    (usually platform-specific) logic."""
+
+    def __init__(self):
+        super(BaseWptScriptAdapter, self).__init__()
+        host = Host()
+        self.port = host.port_factory.get()
+
+    def generate_test_output_args(self, output):
+        return ['--log-chromium', output]
+
+    def generate_sharding_args(self, total_shards, shard_index):
+        return ['--total-chunks=%d' % total_shards,
+                # shard_index is 0-based but WPT's this-chunk to be 1-based
+                '--this-chunk=%d' % (shard_index + 1)]
+
+    def do_post_test_run_tasks(self):
+        # Move json results into layout-test-results directory
+        results_dir = os.path.dirname(self.options.isolated_script_test_output)
+        layout_test_results = os.path.join(results_dir, 'layout-test-results')
+        if os.path.exists(layout_test_results):
+            shutil.rmtree(layout_test_results)
+        os.mkdir(layout_test_results)
+
+        # Perform post-processing of wptrunner output
+        self.process_wptrunner_output()
+
+        shutil.copyfile(self.options.isolated_script_test_output,
+                        os.path.join(layout_test_results, 'full_results.json'))
+        # create full_results_jsonp.js file which is used to
+        # load results into the results viewer
+        with open(self.options.isolated_script_test_output, 'r') \
+            as full_results, \
+            open(os.path.join(
+                layout_test_results, 'full_results_jsonp.js'), 'w') \
+                as json_js:
+            json_js.write('ADD_FULL_RESULTS(%s);' % full_results.read())
+        # copy layout test results viewer to layout-test-results directory
+        shutil.copyfile(
+            os.path.join(WEB_TESTS_DIR, 'fast', 'harness', 'results.html'),
+            os.path.join(layout_test_results, 'results.html'))
+
+    def process_wptrunner_output(self):
+        """Post-process the output generated by wptrunner.
+
+        This output contains a single large json file containing the raw content
+        or artifacts which need to be extracted into their own files and removed
+        from the json file (to avoid duplication)."""
+        output_json = json.load(
+            open(self.options.isolated_script_test_output, "r"))
+        test_json = output_json["tests"]
+        results_dir = os.path.dirname(self.options.isolated_script_test_output)
+        self._process_test_leaves(results_dir, output_json["path_delimiter"],
+                                  test_json, "")
+        # Write output_json back to the same file after modifying it in memory
+        with open(self.options.isolated_script_test_output, "w") as output_file:
+            json.dump(output_json, output_file)
+
+    def _process_test_leaves(self, results_dir, delim, root_node, path_so_far):
+        """Finds and processes each test leaf below the specified root.
+
+        This will recursively traverse the trie of results in the json output,
+        keeping track of the path to each test and identifying leaves by the
+        presence of certain attributes.
+
+        Args:
+            results_dir: str path to the dir that results are stored
+            delim: str delimiter to be used for test names
+            root_node: dict representing the root of the trie we're currently
+                looking at
+            path_so_far: str the path to the current root_node in the trie
+        """
+        if "actual" in root_node:
+            # Found a leaf, process it
+            if "artifacts" not in root_node:
+                return
+            log_artifact = root_node["artifacts"].pop("log", None)
+            if log_artifact:
+                artifact_subpath = self._write_log_artifact(
+                    results_dir, path_so_far, log_artifact)
+                root_node["artifacts"]["actual_text"] = [artifact_subpath]
+
+            screenshot_artifact = root_node["artifacts"].pop("screenshots",
+                                                             None)
+            if screenshot_artifact:
+                screenshot_paths_dict = self._write_screenshot_artifact(
+                    results_dir, path_so_far, screenshot_artifact)
+                for screenshot_key, path in screenshot_paths_dict.items():
+                    root_node["artifacts"][screenshot_key] = [path]
+
+            return
+
+        # We're not at a leaf node, continue traversing the trie.
+        for key in root_node:
+            # Append the key to the path, separated by the delimiter. However if
+            # the path is empty, skip the delimiter to avoid a leading slash in
+            # the path.
+            new_path = path_so_far + delim + key if path_so_far else key
+            self._process_test_leaves(results_dir, delim, root_node[key],
+                                      new_path)
+
+    def _write_log_artifact(self, results_dir, test_name, log_artifact):
+        """Writes a log artifact to disk.
+
+        The log artifact contains all the output of a test. It gets written to
+        the -actual.txt file for the test.
+
+        Args:
+            results_dir: str path to the directory that results live in
+            test_name: str name of the test that this artifact is for
+            log_artifact: list of strings, the log entries for this test from
+                the json output.
+
+        Returns:
+            string path to the artifact file that the log was written to,
+            relative to the directory that the original output is located.
+        """
+        log_artifact_sub_path = (
+            os.path.join("layout-test-results",
+                         self.port.output_filename(
+                             test_name, test_failures.FILENAME_SUFFIX_ACTUAL,
+                             ".txt"))
+        )
+        log_artifact_full_path = os.path.join(results_dir,
+                                              log_artifact_sub_path)
+        if not os.path.exists(os.path.dirname(log_artifact_full_path)):
+            os.makedirs(os.path.dirname(log_artifact_full_path))
+        with open(log_artifact_full_path, "w") as artifact_file:
+            artifact_file.write("\n".join(log_artifact).encode("utf-8"))
+
+        return log_artifact_sub_path
+
+    def _write_screenshot_artifact(self, results_dir, test_name,
+                                   screenshot_artifact):
+        """Write screenshot artifact to disk.
+
+        The screenshot artifact is a list of strings, each of which has the
+        format <url>:<base64-encoded PNG>. Each url-png pair is a screenshot of
+        either the test, or one of its refs. We can identify which screenshot is
+        for the test by comparing the url piece to the test name.
+
+        Args:
+           results_dir: str path to the directory that results live in
+           test:name str name of the test that this artifact is for
+           screenshot_artifact: list of strings, each being a url-png pair as
+               described above.
+
+        Returns:
+             A dict mapping the screenshot key (ie: actual, expected) to the
+             path of the file for that screenshot
+        """
+        result={}
+        for screenshot_pair in screenshot_artifact:
+            screenshot_split = screenshot_pair.split(":")
+            url = screenshot_split[0]
+            # The url produced by wptrunner will have a leading / which we trim
+            # away for easier comparison to the test_name below.
+            if url.startswith("/"):
+                url = url[1:]
+            image_bytes = base64.b64decode(screenshot_split[1].strip())
+
+            screenshot_key = "expected_image"
+            file_suffix = test_failures.FILENAME_SUFFIX_EXPECTED
+            if test_name == url:
+                screenshot_key = "actual_image"
+                file_suffix = test_failures.FILENAME_SUFFIX_ACTUAL
+
+            screenshot_sub_path = (
+                os.path.join("layout-test-results",
+                             self.port.output_filename(
+                                 test_name, file_suffix, ".png"))
+            )
+            result[screenshot_key] = screenshot_sub_path
+
+            screenshot_full_path = os.path.join(results_dir,screenshot_sub_path)
+            if not os.path.exists(os.path.dirname(screenshot_full_path)):
+                os.makedirs(os.path.dirname(screenshot_full_path))
+            # Note: we are writing raw bytes to this file
+            with open(screenshot_full_path, "wb") as artifact_file:
+                artifact_file.write(image_bytes)
+        return result