Use per-frame WebTaskRunner on HTMLMediaElement

third_party/WebKit/Source/core/html/HTMLMediaElement.cpp

Index: third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
diff --git a/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp b/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
index b17a53a2ca6cd96c137b027b624f8128d17f453b..aa0f7cd877c6e3c62a7fe285f5c7d2734de32665 100644
--- a/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
@@ -38,6 +38,7 @@
 #include "core/dom/ElementTraversal.h"
 #include "core/dom/ElementVisibilityObserver.h"
 #include "core/dom/Fullscreen.h"
+#include "core/dom/TaskRunnerHelper.h"
 #include "core/dom/shadow/ShadowRoot.h"
 #include "core/events/Event.h"
 #include "core/frame/FrameView.h"
@@ -3880,8 +3881,8 @@ void HTMLMediaElement::scheduleResolvePlayPromises() {
   if (m_playPromiseResolveTask->isPending())
     return;
 
-  Platform::current()->currentThread()->getWebTaskRunner()->postTask(
-      BLINK_FROM_HERE, m_playPromiseResolveTask->cancelAndCreate());
+  TaskRunnerHelper::get(TaskType::MediaElementEvent, getExecutionContext())

[haraken, 2016/10/13 13:19:38]

Nit: document() is better than getExecutionContext() because
getExecutionContext() can return nullptr (although it won't happen in this
specific case).

[tzik, 2016/10/14 04:15:22]

Done.

+      ->postTask(BLINK_FROM_HERE, m_playPromiseResolveTask->cancelAndCreate());
 }
 
 void HTMLMediaElement::scheduleRejectPlayPromises(ExceptionCode code) {
@@ -3905,8 +3906,8 @@ void HTMLMediaElement::scheduleRejectPlayPromises(ExceptionCode code) {
   // TODO(mlamouri): because cancellable tasks can't take parameters, the
   // error code needs to be saved.
   m_playPromiseErrorCode = code;
-  Platform::current()->currentThread()->getWebTaskRunner()->postTask(
-      BLINK_FROM_HERE, m_playPromiseRejectTask->cancelAndCreate());
+  TaskRunnerHelper::get(TaskType::MediaElementEvent, getExecutionContext())

[haraken, 2016/10/13 13:19:38]

Ditto.

[tzik, 2016/10/14 04:15:22]

Done.

+      ->postTask(BLINK_FROM_HERE, m_playPromiseRejectTask->cancelAndCreate());
 }
 
 void HTMLMediaElement::scheduleNotifyPlaying() {