Intersection Observer support for OOPIF

third_party/WebKit/Source/core/frame/RemoteFrameView.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef RemoteFrameView_h
 #define RemoteFrameView_h
 
+#include "core/dom/IntersectionObserver.h"
 #include "platform/Widget.h"
 #include "platform/geometry/IntRect.h"
 #include "platform/heap/Handle.h"
 
 namespace blink {
 
 class RemoteFrame;
 
 class RemoteFrameView final : public Widget {
  public:
   static RemoteFrameView* create(RemoteFrame*);
 
   ~RemoteFrameView() override;
 
   bool isRemoteFrameView() const override { return true; }
   void setParent(Widget*) override;
 
   RemoteFrame& frame() const {
     ASSERT(m_remoteFrame);
     return *m_remoteFrame;
   }
 
   void dispose() override;
-
   // Override to notify remote frame that its viewport size has changed.
   void frameRectsChanged() override;
-
   void invalidateRect(const IntRect&) override;
-
   void setFrameRect(const IntRect&) override;
-
   void hide() override;
   void show() override;
   void setParentVisible(bool) override;
 
   DECLARE_VIRTUAL_TRACE();
 
  private:
   explicit RemoteFrameView(RemoteFrame*);
 
+  void onViewportIntersectionChanged(
+      const HeapVector<Member<IntersectionObserverEntry>>&);
+  void startIntersectionObserver();
+  void stopIntersectionObserver();
+
   // The properties and handling of the cycle between RemoteFrame
   // and its RemoteFrameView corresponds to that between LocalFrame
   // and FrameView. Please see the FrameView::m_frame comment for
   // details.
   Member<RemoteFrame> m_remoteFrame;
+
+  // An IntersectionObserver is used to monitor the intersection of this
+  // frame with the viewport, which is then forwarded to the remote frame
+  // to enable viewport intersections there to work properly.
+  Member<IntersectionObserver> m_intersectionObserver;
+  IntRect m_lastViewportIntersection;
 };
 
 DEFINE_TYPE_CASTS(RemoteFrameView,
                   Widget,
                   widget,
                   widget->isRemoteFrameView(),
                   widget.isRemoteFrameView());
 
 }  // namespace blink
 
 #endif  // RemoteFrameView_h