Notify WebMediaPlayer when its ancestor enters/exists fullscreen.

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 617bad3cd641e9a7bf1e4b5b9079f621ea4ba1c1..9ad9702945948e0fd9c7b94c2dbaf48d4ec15114 100644
--- a/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLMediaElement.cpp
@@ -37,7 +37,6 @@
 #include "core/dom/DOMException.h"
 #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"
@@ -482,6 +481,8 @@ HTMLMediaElement::HTMLMediaElement(const QualifiedName& tagName,
   addElementToDocumentMap(this, &document);
 
   UseCounter::count(document, UseCounter::HTMLMediaElement);
+
+  Fullscreen::from(document).registerObserver(this);
 }
 
 HTMLMediaElement::~HTMLMediaElement() {
@@ -492,6 +493,8 @@ HTMLMediaElement::~HTMLMediaElement() {
   // the AudioNode is destructed, m_audioSourceNode is explicitly cleared
   // even if the AudioNode and the HTMLMediaElement die together.
   DCHECK(!m_audioSourceNode);
+
+  Fullscreen::from(document()).removeObserver(this);
 }
 
 void HTMLMediaElement::dispose() {
@@ -4098,4 +4101,23 @@ IntRect HTMLMediaElement::AutoplayHelperClientImpl::absoluteBoundingBoxRect()
   return result;
 }
 
+void HTMLMediaElement::onEnteredFullscreen() {
+  if (!webMediaPlayer())
+    return;
+  if (isFullscreen())
+    return;
+
+  Element* fullscreenElement =
+      Fullscreen::currentFullScreenElementFrom(document());
+  if (fullscreenElement->isShadowIncludingInclusiveAncestorOf(this) &&
+      clientWidth() >= document().domWindow()->innerWidth() * 0.9 &&
+      clientHeight() >= document().domWindow()->innerHeight() * 0.9)
+    webMediaPlayer()->enteredFullWindow();
+}
+
+void HTMLMediaElement::onExitedFullscreen() {
+  if (webMediaPlayer())
+    webMediaPlayer()->exitedFullWindow();
+}
+
 }  // namespace blink