Introduce ViewRoot to forward input/view events to native

content/browser/web_contents/web_contents_view_android.h

Index: content/browser/web_contents/web_contents_view_android.h
diff --git a/content/browser/web_contents/web_contents_view_android.h b/content/browser/web_contents/web_contents_view_android.h
index c1ad8dc0a6065561d92d3f937ff69435b045d676..350bb0f72136a03dc661ad1eddcc15c3db93d898 100644
--- a/content/browser/web_contents/web_contents_view_android.h
+++ b/content/browser/web_contents/web_contents_view_android.h
@@ -15,6 +15,7 @@
 #include "content/public/common/drop_data.h"
 #include "ui/android/overscroll_refresh.h"
 #include "ui/android/view_android.h"
+#include "ui/android/view_client.h"
 #include "ui/gfx/geometry/rect_f.h"
 
 namespace content {
@@ -24,7 +25,8 @@ class WebContentsImpl;
 
 // Android-specific implementation of the WebContentsView.
 class WebContentsViewAndroid : public WebContentsView,
-                               public RenderViewHostDelegateView {
+                               public RenderViewHostDelegateView,
+                               public ui::ViewClient {
  public:
   WebContentsViewAndroid(WebContentsImpl* web_contents,
                          WebContentsViewDelegate* delegate);
@@ -71,6 +73,9 @@ class WebContentsViewAndroid : public WebContentsView,
   void RenderViewSwappedIn(RenderViewHost* host) override;
   void SetOverscrollControllerEnabled(bool enabled) override;
 
+  // ui::ViewClient implementation.
+  void OnPhysicalBackingSizeChanged(int width, int height) override;
+
   // Backend implementation of RenderViewHostDelegateView.
   void ShowContextMenu(RenderFrameHost* render_frame_host,
                        const ContextMenuParams& params) override;