Visual viewport API initial implementation.

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

Index: third_party/WebKit/Source/core/dom/Document.h
diff --git a/third_party/WebKit/Source/core/dom/Document.h b/third_party/WebKit/Source/core/dom/Document.h
index b8c2865e2ed49791223acdb992c35b55ac94c368..5b386a67769ba26f109d7fd5386e973cf6ee5770 100644
--- a/third_party/WebKit/Source/core/dom/Document.h
+++ b/third_party/WebKit/Source/core/dom/Document.h
@@ -51,6 +51,7 @@
 #include "core/frame/DOMTimerCoordinator.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "core/frame/OriginsUsingFeatures.h"
+#include "core/frame/VisualViewport.h"
 #include "core/html/CollectionType.h"
 #include "core/html/parser/ParserSynchronizationPolicy.h"
 #include "core/page/PageVisibilityState.h"
@@ -298,6 +299,7 @@ public:
     WillBeHeapVector<RawPtrWillBeMember<Element>> elementsFromPoint(int x, int y) const;
     PassRefPtrWillBeRawPtr<Range> caretRangeFromPoint(int x, int y);
     Element* scrollingElement();
+    VisualViewport* visualViewport();
 
     String readyState() const;
 
@@ -903,6 +905,7 @@ public:
     // Only one event for a target/event type combination will be dispatched per frame.
     void enqueueUniqueAnimationFrameEvent(PassRefPtrWillBeRawPtr<Event>);
     void enqueueMediaQueryChangeListeners(WillBeHeapVector<RefPtrWillBeMember<MediaQueryListListener>>&);
+    void enqueueVisualViewportChangedEvent();
 
     void dispatchEventsForPrinting();