Added the infrastructure for surfaceProxy.onResize() and SurfaceView.onResize()

extensions/renderer/guest_view/guest_view_internal_custom_bindings.h

Index: extensions/renderer/guest_view/guest_view_internal_custom_bindings.h
diff --git a/extensions/renderer/guest_view/guest_view_internal_custom_bindings.h b/extensions/renderer/guest_view/guest_view_internal_custom_bindings.h
index b679aeca47645e782ca4a5fccf808b1ba30e107f..0c29435f411e6e029cea109fe61fd3480cf7362f 100644
--- a/extensions/renderer/guest_view/guest_view_internal_custom_bindings.h
+++ b/extensions/renderer/guest_view/guest_view_internal_custom_bindings.h
@@ -45,6 +45,12 @@ class GuestViewInternalCustomBindings : public ObjectBackedNativeHandler {
   // RegisterDestructionCallback takes in a single paramater, |callback|.
   void RegisterDestructionCallback(
       const v8::FunctionCallbackInfo<v8::Value>& args);
+
+  // RegisterElementResizeCallback registers a JavaScript callback function to
+  // be called when the element is resized. RegisterElementResizeCallback takes
+  // a single parameter, |callback|.
+  void RegisterElementResizeCallback(
+      const v8::FunctionCallbackInfo<v8::Value>& args);
 };
 
 }  // namespace extensions