Convert m_deferredLoadTimer to Unthrottled frame-specific timer and include in didMoveToNewDocument.

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 ee9fcef69378dead67b65cea6c7dc6d80c76c054..2d5368310a7d1fed43177bf022b3c9c934397cfd 100644
--- a/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
@@ -428,7 +428,10 @@ HTMLMediaElement::HTMLMediaElement(const QualifiedName& tagName,
       m_defaultPlaybackStartPosition(0),
       m_loadState(WaitingForSource),
       m_deferredLoadState(NotDeferred),
-      m_deferredLoadTimer(this, &HTMLMediaElement::deferredLoadTimerFired),
+      m_deferredLoadTimer(
+          TaskRunnerHelper::get(TaskType::Unthrottled, &document),
+          this,
+          &HTMLMediaElement::deferredLoadTimerFired),
       m_webLayer(nullptr),
       m_displayMode(Unknown),
       m_officialPlaybackPosition(0),
@@ -506,17 +509,19 @@ void HTMLMediaElement::didMoveToNewDocument(Document& oldDocument) {
   BLINK_MEDIA_LOG << "didMoveToNewDocument(" << (void*)this << ")";
 
   m_loadTimer.moveToNewTaskRunner(
-      TaskRunnerHelper::get(TaskType::Unthrottled, &document()));
+      TaskRunnerHelper::get(TaskType::MediaElementEvent, &document()));
   m_progressEventTimer.moveToNewTaskRunner(
-      TaskRunnerHelper::get(TaskType::Unthrottled, &document()));
+      TaskRunnerHelper::get(TaskType::MediaElementEvent, &document()));
   m_playbackProgressTimer.moveToNewTaskRunner(
-      TaskRunnerHelper::get(TaskType::Unthrottled, &document()));
+      TaskRunnerHelper::get(TaskType::MediaElementEvent, &document()));
   m_audioTracksTimer.moveToNewTaskRunner(
-      TaskRunnerHelper::get(TaskType::Unthrottled, &document()));
+      TaskRunnerHelper::get(TaskType::MediaElementEvent, &document()));
   m_viewportFillDebouncerTimer.moveToNewTaskRunner(
-      TaskRunnerHelper::get(TaskType::Unthrottled, &document()));
+      TaskRunnerHelper::get(TaskType::MediaElementEvent, &document()));
   m_checkViewportIntersectionTimer.moveToNewTaskRunner(
-      TaskRunnerHelper::get(TaskType::Unthrottled, &document()));
+      TaskRunnerHelper::get(TaskType::MediaElementEvent, &document()));

[haraken, 2017/02/27 07:50:45]

Is this your intentional change? You're changing existing Unthrottled timers to
MediaElementEvent timers.

[foolip, 2017/02/27 15:39:08]

Most of these changes are probably correct, but some probably refer to bits that
don't correspond to a "queue a task" in the spec. Joel, can you go through the
call sites to see which aren't obviously spec algorithms of the sort quoted
below, and say something about those cases?

+  m_deferredLoadTimer.moveToNewTaskRunner(
+      TaskRunnerHelper::get(TaskType::MediaElementEvent, &document()));

[foolip, 2017/02/27 15:39:08]

At the m_deferredLoadTimer.startOneShot call site we are inside
HTMLMediaElement::deferLoad() which implements a spec algorithm
https://html.spec.whatwg.org/multipage/embedded-content.html#concept-media-lo...
which should use the "media element event task source" because "Except where
otherwise explicitly specified, the task source for all the tasks queued in this
section and its subsections is the media element event task source of the media
element in question."

So, this bit is correct.

 
   m_autoplayUmaHelper->didMoveToNewDocument(oldDocument);
   // If any experiment is enabled, then we want to enable a user gesture by