Normalize top controls offset to (0, 1), Chromium-side.

mojo/services/html_viewer/weblayertreeview_impl.h

Index: mojo/services/html_viewer/weblayertreeview_impl.h
diff --git a/mojo/services/html_viewer/weblayertreeview_impl.h b/mojo/services/html_viewer/weblayertreeview_impl.h
index 42ae1bc2f7dc7c5ca8c6da6fa776b9bdf887ada7..8a5d89f15caa3986de577a0b8cc492a570c125a0 100644
--- a/mojo/services/html_viewer/weblayertreeview_impl.h
+++ b/mojo/services/html_viewer/weblayertreeview_impl.h
@@ -89,6 +89,7 @@ class WebLayerTreeViewImpl : public blink::WebLayerTreeView,
                                        double duration_sec);
   virtual void heuristicsForGpuRasterizationUpdated(bool matches_heuristic) {}
   virtual void setTopControlsContentOffset(float offset) {}
+  virtual void setTopControlsShownRatio(float ratio) {}
   virtual void setNeedsAnimate();
   virtual bool commitRequested() const;
   virtual void didStopFlinging() {}