Start autoplay muted videos with autoplay attribute when they are visible.

third_party/WebKit/Source/core/dom/IntersectionObserver.h

Index: third_party/WebKit/Source/core/dom/IntersectionObserver.h
diff --git a/third_party/WebKit/Source/core/dom/IntersectionObserver.h b/third_party/WebKit/Source/core/dom/IntersectionObserver.h
index ecf68c3c88f1a9575bc22476d4c0671976b3b6c8..56376480da1beb056dee1e453ee9aeeb6d77f27c 100644
--- a/third_party/WebKit/Source/core/dom/IntersectionObserver.h
+++ b/third_party/WebKit/Source/core/dom/IntersectionObserver.h
@@ -28,17 +28,23 @@ public:
     static IntersectionObserver* create(const IntersectionObserverInit&, IntersectionObserverCallback&, ExceptionState&);
     static void resumeSuspendedObservers();
 
-    // API methods
+    IntersectionObserver(IntersectionObserverCallback&, Node&, const Vector<Length>& rootMargin, const Vector<float>& thresholds);
+
+    // JS API methods.
     void observe(Element*, ExceptionState&);

[esprehn, 2016/06/14 16:01:18]

void observe(Element*, ExceptionState& = ASSERT_NO_EXCEPTION);
void unobserve(Element*, ExceptionState& = ASSERT_NO_EXCEPTION);

     void unobserve(Element*, ExceptionState&);
     void disconnect(ExceptionState&);
     HeapVector<Member<IntersectionObserverEntry>> takeRecords(ExceptionState&);
 
-    // API attributes
+    // JS API attributes.
     Element* root() const;
     String rootMargin() const;
     const Vector<float>& thresholds() const { return m_thresholds; }
 
+    // C++ API methods.
+    void observe(Element*);
+    void unobserve(Element*);

[esprehn, 2016/06/14 16:01:18]

remove

+
     Node* rootNode() const { return m_root.get(); }
     LayoutObject* rootLayoutObject() const;
     const Length& topMargin() const { return m_topMargin; }
@@ -57,7 +63,6 @@ public:
     DECLARE_TRACE();
 
 private:
-    explicit IntersectionObserver(IntersectionObserverCallback&, Node&, const Vector<Length>& rootMargin, const Vector<float>& thresholds);
     void clearWeakMembers(Visitor*);
 
     Member<IntersectionObserverCallback> m_callback;