Fix main thread top controls scrolling to mirror CC.

content/renderer/render_view_impl.h

Index: content/renderer/render_view_impl.h
diff --git a/content/renderer/render_view_impl.h b/content/renderer/render_view_impl.h
index c3688b5650394ce5aed1e646331ca3289374778f..ee6d6b30d1b180552b3af05f40bf24d7c016366c 100644
--- a/content/renderer/render_view_impl.h
+++ b/content/renderer/render_view_impl.h
@@ -472,6 +472,7 @@ class CONTENT_EXPORT RenderViewImpl
   void DidCommitCompositorFrame() override;
   void DidCompletePageScaleAnimation() override;
   void OnDeviceScaleFactorChanged() override;
+  void ResizeWebWidget(const ResizeParams& params) override;
 
   RenderViewImpl(CompositorDependencies* compositor_deps,
                  const ViewMsg_New_Params& params);
@@ -863,6 +864,13 @@ class CONTENT_EXPORT RenderViewImpl
   TopControlsState top_controls_constraints_;
 #endif
 
+  // Whether or not Blink's viewport size should be shrunk by the height of the
+  // URL-bar.
+  bool top_controls_shrink_blink_size_;
+
+  // The height of the top controls.
+  float top_controls_height_;
+
   // Indicates whether this page has been focused/unfocused by the browser.
   bool has_focus_;