BASELINE: Update Chromium to 59.0.3071.134

Change-Id: Id02ef6fb2204c5fd21668a1c3e6911c83b17585a
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

1 files changed, 35 insertions, 17 deletions

diff --git a/chromium/components/background_task_scheduler/README.md b/chromium/components/background_task_scheduler/README.md
index c48720d51da..bc83b48d005 100644
--- a/chromium/components/background_task_scheduler/README.md
+++ b/chromium/components/background_task_scheduler/README.md
@@ -7,21 +7,39 @@ instead of using things like `IntentService` or polling using alarms. Using the
 system API is beneficial as it has a full view of what goes on in the system and
 can schedule jobs accordingly.
 
-However, this functionality was introduced in Android L, and
-the API has been very stable since Android M. This means that we also need a
-similar framework for older versions of Android, which is provided by
-Google Play services. We prefer system APIs, since they do not require including
-external libraries which bloats the APK size of Chrome and adds unnecessary
-complexity. The GcmNetworkManager is only used when the system API is not
-available.
-
-The `background_task_scheduler` component provides a new framework for use
-within chromium to schedule and execute background jobs using the frameworks
-available on a given version of Android.
-The public API of the framework is similar to that of the Android
-`JobScheduler`, but it is backed by either the system `JobScheduler` API or by
-GcmNetworkManager. What service is used to back the framework remains unknown to
-callers of the API.
+However, that leaves an API gap for Android L and below. Prior to Android L, the
+`JobScheduler` API was not available at all. It was introduced in Android L; but
+is not recommended on that platform, because it limits task execution time to 1
+minute. This is not really practically usable. For example, merely setting up a
+network connection will often burn through much of that budget. Android M+
+extends this execution time limit to 10 minutes.
+
+For these older platforms, we can leverage the GcmNetworkManager API provided by
+Google Play services to implement a suitable replacement for the JobScheduler
+API. The `background_task_scheduler` component provides a new framework for use
+within Chromium to schedule and execute background jobs using the frameworks
+available on a given version of Android. The public API of the framework is
+similar to that of the Android `JobScheduler`, but it is backed by either the
+system `JobScheduler` API or by GcmNetworkManager. What service is used to back
+the framework remains a black box to callers of the API.
+
+In practice, we prefer to use system APIs, since they do not require including
+external libraries, which would bloat the APK size of Chrome and add unnecessary
+complexity. Thus, the GcmNetworkManager is only used when the system API is not
+available (or available but not considered stable enough). That is, the
+JobScheduler API is used on Android M+; and the GcmNetworkManager is used
+otherwise.
+
+> **WARNING: The GcmNetworkManager fallback is not yet implemented.** Please
+> treat the above as a target state, and do not yet add any dependencies on the
+> BackgroundTaskScheduler API that require pre-M compatibility.
+
+> NOTE: Even with the GcmNetworkManager fallback, there are devices that would
+> remain unsupported, as not all devices have Google Play services
+> available. Ultimately, this component hopes to provide a full compatibility
+> layer on top of `JobScheduler`. However, until that is implemented, please be
+> thoughtful about whether this component provides the coverage that your
+> background task needs.
 
 ## What is a task
 
@@ -95,14 +113,14 @@ When the task is ready for scheduling, you use the
 `BackgroundTaskScheduler` and use it to schedule the job.
 
 ```java
-BackgroundTaskScheduleFactory.getScheduler().schedule(myTaskInfo);
+BackgroundTaskSchedulerFactory.getScheduler().schedule(myTaskInfo);
 ```
 
 If you ever need to cancel a task, you can do that by calling `cancel`, and
 passing in the task ID:
 
 ```java
-BackgroundTaskScheduleFactory.getScheduler().cancel(TaskIds.YOUR_FEATURE);
+BackgroundTaskSchedulerFactory.getScheduler().cancel(TaskIds.YOUR_FEATURE);
 ```
 
 ## Passing task arguments