Move surface resize platform code from GpuProcessHostUIShim to RenderWidgetHostView implementations.

content/port/browser/render_widget_host_view_port.h

Index: content/port/browser/render_widget_host_view_port.h
diff --git a/content/port/browser/render_widget_host_view_port.h b/content/port/browser/render_widget_host_view_port.h
index 1e0ba5b38402400f0f3610b03a051bedca80f0b8..f9444b3fe3efdca34ced3389ad9099a5dc208b36 100644
--- a/content/port/browser/render_widget_host_view_port.h
+++ b/content/port/browser/render_widget_host_view_port.h
@@ -255,6 +255,9 @@ class CONTENT_EXPORT RenderWidgetHostViewPort : public RenderWidgetHostView,
 
   virtual gfx::GLSurfaceHandle GetCompositingSurface() = 0;
 
+  // Resize compositing surface.
+  virtual void ResizeCompositingSurface(const gfx::Size&) = 0;
+
   // Because the associated remote WebKit instance can asynchronously
   // prevent-default on a dispatched touch event, the touch events are queued in
   // the GestureRecognizer until invocation of ProcessAckedTouchEvent releases