aura: fix hang when the content window is removed from the tree while a swap is pending

content/browser/renderer_host/render_widget_host_view_aura.h

Index: content/browser/renderer_host/render_widget_host_view_aura.h
diff --git a/content/browser/renderer_host/render_widget_host_view_aura.h b/content/browser/renderer_host/render_widget_host_view_aura.h
index 66b379659a7629967b21c46518879e8cb222da68..3123c56e98e6ae26eee88296b848c95d89946e64 100644
--- a/content/browser/renderer_host/render_widget_host_view_aura.h
+++ b/content/browser/renderer_host/render_widget_host_view_aura.h
@@ -205,6 +205,12 @@ class RenderWidgetHostViewAura
   // moved to center.
   bool ShouldMoveToCenter();
 
+  // Run the compositing callbacks.
+  void RunCompositingCallbacks();
+
+  // Called when window_ is removed from the window tree.
+  void RemovingFromRootWindow();
+
   ui::Compositor* GetCompositor();
 
   // The model object.