1 files changed, 92 insertions, 0 deletions
diff --git a/chromium/third_party/blink/renderer/modules/video_rvfc/video_frame_request_callback_collection.cc b/chromium/third_party/blink/renderer/modules/video_rvfc/video_frame_request_callback_collection.cc
new file mode 100644
index 00000000000..b9676a22842
--- /dev/null
+++ b/chromium/third_party/blink/renderer/modules/video_rvfc/video_frame_request_callback_collection.cc
@@ -0,0 +1,92 @@
+// Copyright 2019 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.
+
+#include "third_party/blink/renderer/modules/video_rvfc/video_frame_request_callback_collection.h"
+
+#include "third_party/blink/renderer/core/inspector/inspector_trace_events.h"
+#include "third_party/blink/renderer/core/probe/core_probes.h"
+
+namespace blink {
+
+VideoFrameRequestCallbackCollection::VideoFrameRequestCallbackCollection(
+    ExecutionContext* context)
+    : context_(context) {}
+
+VideoFrameRequestCallbackCollection::CallbackId
+VideoFrameRequestCallbackCollection::RegisterFrameCallback(
+    VideoFrameCallback* callback) {
+  VideoFrameRequestCallbackCollection::CallbackId id = ++next_callback_id_;
+  callback->SetIsCancelled(false);
+  callback->SetId(id);
+  frame_callbacks_.push_back(callback);
+
+  return id;
+}
+
+void VideoFrameRequestCallbackCollection::CancelFrameCallback(CallbackId id) {
+  for (wtf_size_t i = 0; i < frame_callbacks_.size(); ++i) {
+    if (frame_callbacks_[i]->Id() == id) {
+      frame_callbacks_.EraseAt(i);
+      return;
+    }
+  }
+  for (const auto& callback : callbacks_to_invoke_) {
+    if (callback->Id() == id) {
+      callback->SetIsCancelled(true);
+      // will be removed at the end of ExecuteCallbacks().
+      return;
+    }
+  }
+}
+
+void VideoFrameRequestCallbackCollection::ExecuteFrameCallbacks(
+    double high_res_now_ms,
+    const VideoFrameMetadata* metadata) {
+  // First, generate a list of callbacks to consider. Callbacks registered from
+  // this point on are considered only for the "next" frame, not this one.
+  DCHECK(callbacks_to_invoke_.IsEmpty());
+  std::swap(callbacks_to_invoke_, frame_callbacks_);
+
+  for (const auto& callback : callbacks_to_invoke_) {
+    // When the ExecutionContext is destroyed (e.g. an iframe is detached),
+    // there is no path to perform wrapper tracing for the callbacks. In such a
+    // case, the callback functions may already have been collected by V8 GC.
+    // Since it's possible that a callback function being invoked detaches an
+    // iframe, we need to check the condition for each callback.
+    if (context_->IsContextDestroyed())
+      break;
+
+    // Another requestAnimationFrame callback already cancelled this one.
+    if (callback->IsCancelled())
+      continue;
+
+    callback->Invoke(high_res_now_ms, metadata);
+  }
+
+  callbacks_to_invoke_.clear();
+}
+
+void VideoFrameRequestCallbackCollection::Trace(Visitor* visitor) {
+  visitor->Trace(frame_callbacks_);
+  visitor->Trace(callbacks_to_invoke_);
+  visitor->Trace(context_);
+}
+
+VideoFrameRequestCallbackCollection::V8VideoFrameCallback::V8VideoFrameCallback(
+    V8VideoFrameRequestCallback* callback)
+    : callback_(callback) {}
+
+void VideoFrameRequestCallbackCollection::V8VideoFrameCallback::Trace(
+    blink::Visitor* visitor) {
+  visitor->Trace(callback_);
+  VideoFrameRequestCallbackCollection::VideoFrameCallback::Trace(visitor);
+}
+
+void VideoFrameRequestCallbackCollection::V8VideoFrameCallback::Invoke(
+    double highResTime,
+    const VideoFrameMetadata* metadata) {
+  callback_->InvokeAndReportException(nullptr, highResTime, metadata);
+}
+
+}  // namespace blink