When short-circuiting resize requests, keep track what the browser thinks the current size is

content/renderer/render_widget.h

Index: content/renderer/render_widget.h
diff --git a/content/renderer/render_widget.h b/content/renderer/render_widget.h
index 3660f75d57c2a3636a61edd176e106dcd4db4f43..2ab778c82ff41932cf3888e03f72711716a59b2d 100644
--- a/content/renderer/render_widget.h
+++ b/content/renderer/render_widget.h
@@ -529,6 +529,12 @@ class CONTENT_EXPORT RenderWidget
   // The size of the RenderWidget.
   gfx::Size size_;
 
+  // When short-circuiting size updates, the browser might not know about the
+  // current size of the RenderWidget. To be able to correctly predict when the
+  // browser expects a resize ack, keep track of the size the browser thinks
+  // this RenderWidget should have.
+  gfx::Size size_browser_expects_;
+
   // The TransportDIB that is being used to transfer an image to the browser.
   TransportDIB* current_paint_buf_;