Reland "Implement FullScreen using top layer."

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

Index: third_party/WebKit/Source/core/dom/Fullscreen.h
diff --git a/third_party/WebKit/Source/core/dom/Fullscreen.h b/third_party/WebKit/Source/core/dom/Fullscreen.h
index a624c20a86c31f2f39313727198a5d3e1a00207b..8818a1ed8580c5ec12a11f94539227dd99989b52 100644
--- a/third_party/WebKit/Source/core/dom/Fullscreen.h
+++ b/third_party/WebKit/Source/core/dom/Fullscreen.h
@@ -41,7 +41,6 @@
 
 namespace blink {
 
-class LayoutFullScreen;
 class ComputedStyle;
 
 class CORE_EXPORT Fullscreen final
@@ -86,9 +85,7 @@ public:
     void didEnterFullScreenForElement(Element*);
     void didExitFullScreenForElement();
 
-    void setFullScreenLayoutObject(LayoutFullScreen*);
-    LayoutFullScreen* fullScreenLayoutObject() const { return m_fullScreenLayoutObject; }
-    void fullScreenLayoutObjectDestroyed();
+    void didUpdateSize(Element&);
 
     void elementRemoved(Element&);
 
@@ -104,6 +101,9 @@ public:
 
     DECLARE_VIRTUAL_TRACE();
 
+    using ElementStack = HeapVector<std::pair<Member<Element>, RequestType>>;
+    const ElementStack& fullScreenElementStack() const { return m_fullScreenElementStack; }
+
 private:
     static Fullscreen* fromIfExistsSlow(Document&);
 
@@ -121,7 +121,6 @@ private:
 
     Member<Element> m_fullScreenElement;
     HeapVector<std::pair<Member<Element>, RequestType>> m_fullScreenElementStack;
-    LayoutFullScreen* m_fullScreenLayoutObject;
     Timer<Fullscreen> m_eventQueueTimer;
     HeapDeque<Member<Event>> m_eventQueue;
     LayoutRect m_savedPlaceholderFrameRect;