Introduce ViewRoot to forward input/view events to native

content/browser/web_contents/web_contents_view_android.cc

Index: content/browser/web_contents/web_contents_view_android.cc
diff --git a/content/browser/web_contents/web_contents_view_android.cc b/content/browser/web_contents/web_contents_view_android.cc
index 748b6103474205c8704f323e170f89e6f545e027..bd42f3ca0e4c3e1c2945985919d81a7770dd1998 100644
--- a/content/browser/web_contents/web_contents_view_android.cc
+++ b/content/browser/web_contents/web_contents_view_android.cc
@@ -84,6 +84,7 @@ WebContentsViewAndroid::WebContentsViewAndroid(
     : web_contents_(web_contents),
       content_view_core_(NULL),
       delegate_(delegate),
+      view_(this),
       synchronous_compositor_client_(nullptr) {
 }
 
@@ -263,6 +264,12 @@ void WebContentsViewAndroid::RenderViewSwappedIn(RenderViewHost* host) {
 void WebContentsViewAndroid::SetOverscrollControllerEnabled(bool enabled) {
 }
 
+void WebContentsViewAndroid::OnPhysicalBackingSizeChanged(int width,
+                                                          int height) {
+  // |SendScreenRects()| indirectly calls GetViewSize() that asks Java layer.
+  web_contents_->SendScreenRects();
+}
+
 void WebContentsViewAndroid::ShowContextMenu(
     RenderFrameHost* render_frame_host, const ContextMenuParams& params) {
   if (delegate_)