Store physical backing size in ViewAndroid

ui/android/view_android.h

 // Copyright 2013 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 UI_ANDROID_VIEW_ANDROID_H_
 #define UI_ANDROID_VIEW_ANDROID_H_
 
 #include <list>
 
 #include "base/android/jni_weak_ref.h"
@@ skipping 91 matching lines @@
     return content_offset_;
   }
 
   // Returns the window at the root of this hierarchy, or |null|
   // if disconnected.
   virtual WindowAndroid* GetWindowAndroid() const;
 
   // Used to return and set the layer for this view. May be |null|.
   cc::Layer* GetLayer() const;
   void SetLayer(scoped_refptr<cc::Layer> layer);
+  void UpdateLayerBounds();
 
   void SetDelegate(const base::android::JavaRef<jobject>& delegate);
 
   // Gets (creates one if not present) Java object of the EventForwarder
   // for a view tree in the view hierarchy including this node.
   // Only one instance per the view tree is allowed.
   base::android::ScopedJavaLocalRef<jobject> GetEventForwarder();
 
   // Adds a child to this view.
   void AddChild(ViewAndroid* child);
 
   // Moves the give child ViewAndroid to the front of the list so that it can be
   // the first responder of events.
   void MoveToFront(ViewAndroid* child);
 
   // Detaches this view from its parent.
   void RemoveFromParent();
 
   // Sets the layout relative to parent. Used to do hit testing against events.
   void SetLayout(LayoutParams params);
 
   bool StartDragAndDrop(const base::android::JavaRef<jstring>& jtext,
                         const base::android::JavaRef<jobject>& jimage);
 
+  gfx::Size GetPhysicalBackingSize();
+  void OnPhysicalBackingSizeChanged(const gfx::Size& size);

[boliu, 2017/04/29 00:18:40]

does this need to be public?

[Jinsuk Kim, 2017/04/30 00:23:50]

Yes. The other OnXXX calls are from event forwarder which is a friend of this
class.

   void OnBackgroundColorChanged(unsigned int color);
   void OnTopControlsChanged(float top_controls_offset,
                             float top_content_offset);
   void OnBottomControlsChanged(float bottom_controls_offset,
                                float bottom_content_offset);
   int GetSystemWindowInsetBottom();
 
   ScopedAnchorView AcquireAnchorView();
   void SetAnchorRect(const base::android::JavaRef<jobject>& anchor,
                      const gfx::RectF& bounds);
@@ skipping 48 matching lines @@
   std::list<ViewAndroid*> children_;
   scoped_refptr<cc::Layer> layer_;
   JavaObjectWeakGlobalRef delegate_;
 
   ViewClient* const client_;
 
   // Basic view layout information. Used to do hit testing deciding whether
   // the passed events should be processed by the view.
   LayoutParams layout_params_;
 
+  gfx::Size physical_size_;
+
   gfx::Vector2dF content_offset_;  // in CSS pixel.
   std::unique_ptr<EventForwarder> event_forwarder_;
 
   DISALLOW_COPY_AND_ASSIGN(ViewAndroid);
 };
 
 }  // namespace ui
 
 #endif  // UI_ANDROID_VIEW_ANDROID_H_