Include viewport visibility checks for autoplay experiment.

third_party/WebKit/Source/core/layout/LayoutMedia.cpp

Index: third_party/WebKit/Source/core/layout/LayoutMedia.cpp
diff --git a/third_party/WebKit/Source/core/layout/LayoutMedia.cpp b/third_party/WebKit/Source/core/layout/LayoutMedia.cpp
index 374c4b1889cb25e1e8043d9c099085f857c5906d..4d7740e9711694e47f555bef52e71af1825defba 100644
--- a/third_party/WebKit/Source/core/layout/LayoutMedia.cpp
+++ b/third_party/WebKit/Source/core/layout/LayoutMedia.cpp
@@ -35,6 +35,8 @@ namespace blink {
 
 LayoutMedia::LayoutMedia(HTMLMediaElement* video)
     : LayoutImage(video)
+    , m_registeredForPositionChangeNotifications(false)
+    , m_wantPositionChangeNotifications(false)
 {
     setImageResource(LayoutImageResource::create());
 }
@@ -119,4 +121,60 @@ void LayoutMedia::paintReplaced(const PaintInfo&, const LayoutPoint&)
 {
 }
 
+void LayoutMedia::willBeDestroyed()
+{
+    updatePositionChangeRegistration(false);

[esprehn, 2015/10/01 07:04:14]

inline the remove case here

[liberato (no reviews please), 2015/10/01 22:49:02]

Done.

+    LayoutImage::willBeDestroyed();
+}
+
+void LayoutMedia::insertedIntoTree()
+{
+    LayoutImage::insertedIntoTree();
+
+    // Note that if we don't want them and aren't registered, then this
+    // will do nothing.
+    updatePositionChangeRegistration(m_wantPositionChangeNotifications);

[esprehn, 2015/10/01 07:04:14]

remove this, you don't need to hook inserted at all

[liberato (no reviews please), 2015/10/01 22:49:02]

inserted is needed to catch cases where an element is removed and re-added to
the tree via JS.

+}
+
+void LayoutMedia::willBeRemovedFromTree()

[esprehn, 2015/10/01 07:04:14]

why do you hook removal? I don't think you need this, just destroyed

[liberato (no reviews please), 2015/10/01 22:49:02]

Done.

+{
+    // Note that if we don't want them and/or aren't registered, then this
+    // will do nothing.
+    updatePositionChangeRegistration(false);
+
+    LayoutImage::willBeRemovedFromTree();
+}
+
+void LayoutMedia::notifyPositionMayHaveChanged()
+{
+    // Tell our element about it.
+    if (HTMLMediaElement* element = mediaElement())
+        element->notifyPositionMayHaveChanged();
+}
+
+void LayoutMedia::updatePositionChangeRegistration(bool doRegister)
+{
+    // If we don't have a view, then take no action.
+    if (!view())

[ojan, 2015/10/01 06:14:26]

Pretty sure this isn't possible.

[liberato (no reviews please), 2015/10/01 22:49:02]

it does happen during the test:

#0 0x000000463b2b base::debug::(anonymous namespace)::StackDumpSignalHandler()
#1 0x7f12c31c6340 <unknown>
#2 0x000001aa8454
blink::LayoutView::unregisterMediaForPositionChangeNotification()
#3 0x000001a5e8af blink::LayoutMedia::willBeDestroyed()
#4 0x000001a6e02d blink::LayoutObject::destroy()
#5 0x0000014bf081 blink::Node::detach()
#6 0x0000014782c8 blink::ContainerNode::detach()
#7 0x0000014a69a5 blink::Element::detach()
#8 0x0000014782af blink::ContainerNode::detach()
#9 0x0000014a69a5 blink::Element::detach()
#10 0x0000014782af blink::ContainerNode::detach()
#11 0x0000014a69a5 blink::Element::detach()
#12 0x0000014782af blink::ContainerNode::detach()
#13 0x0000014a69a5 blink::Element::detach()
#14 0x0000014782af blink::ContainerNode::detach()
#15 0x00000148cf74 blink::Document::detach()
#16 0x00000189c855 blink::FrameLoader::prepareForCommit()
#17 0x00000189c9e2 blink::FrameLoader::commitProvisionalLoad()
#18 0x00000188bc1a blink::DocumentLoader::finishedLoading()
#19 0x00000188dc3f blink::DocumentLoader::maybeLoadEmpty()
#20 0x00000188e0e0 blink::DocumentLoader::startLoadingMainResource()
#21 0x00000189c1a8 blink::FrameLoader::startLoad()
#22 0x000001899751 blink::FrameLoader::load()
#23 0x00000103eb75 blink::WebLocalFrameImpl::load()
#24 0x00000103ec23 blink::WebLocalFrameImpl::loadRequest()
#25 0x000000450d5f content::BlinkTestRunner::OnReset()
#26 0x0000004507b3 content::BlinkTestRunner::OnMessageReceived()
#27 0x0000022bfad6 content::RenderViewImpl::OnMessageReceived()
#28 0x00000265ef43 content::MessageRouter::RouteMessage()
#29 0x00000265eee9 content::MessageRouter::OnMessageReceived()
#30 0x000002235624 content::ChildThreadImpl::OnMessageReceived()
#31 0x000002690f8c IPC::ChannelProxy::Context::OnDispatchMessage()
#32 0x0000004aa0ed base::debug::TaskAnnotator::RunTask()
#33 0x00000228c148 scheduler::TaskQueueManager::ProcessTaskFromWorkQueue()
#34 0x00000228ad0e scheduler::TaskQueueManager::DoWork()
#35 0x0000004aa0ed base::debug::TaskAnnotator::RunTask()
#36 0x00000047042b base::MessageLoop::RunTask()
#37 0x000000470739 base::MessageLoop::DeferOrRunPendingTask()
#38 0x00000047091d base::MessageLoop::DoWork()
#39 0x000000471c6a base::MessagePumpDefault::Run()
#40 0x00000047bcd0 base::RunLoop::Run()
#41 0x00000046fb8a base::MessageLoop::Run()
#42 0x0000022da4a4 content::RendererMain()
#43 0x000000453b17 content::RunZygote()
#44 0x0000004547f1 content::ContentMainRunnerImpl::Run()
#45 0x000000453790 content::ContentMain()

+        return;
+
+    // If our registration state matches the incoming state, then no work
+    // is needed.
+    if (doRegister == m_registeredForPositionChangeNotifications)
+        return;
+
+    if (doRegister)

[esprehn, 2015/10/01 07:04:14]

Remove this method

[liberato (no reviews please), 2015/10/01 22:49:03]

Done.

+        view()->registerMediaForPositionChangeNotification(this);
+    else
+        view()->unregisterMediaForPositionChangeNotification(this);
+
+    m_registeredForPositionChangeNotifications = doRegister;
+}
+
+void LayoutMedia::setRequestPositionUpdates(bool want)
+{
+    m_wantPositionChangeNotifications = want;
+    updatePositionChangeRegistration(m_wantPositionChangeNotifications);

[esprehn, 2015/10/01 07:04:14]

inline the positive case here

[liberato (no reviews please), 2015/10/01 22:49:02]

Done, though both cases are used.

+}
+
 } // namespace blink