Disambiguate OnMouseCaptureLost from OnMouseReleased, etc.

views/controls/button/button_dropdown.h

Index: views/controls/button/button_dropdown.h
diff --git a/views/controls/button/button_dropdown.h b/views/controls/button/button_dropdown.h
index 0a6258497ec280e3f299fa7125ebb16df6092f71..9e8785c22c4a74885e7ab721bc6840867141dffb 100644
--- a/views/controls/button/button_dropdown.h
+++ b/views/controls/button/button_dropdown.h
@@ -28,7 +28,9 @@ class ButtonDropDown : public ImageButton {
   // Overridden from views::View
   virtual bool OnMousePressed(const MouseEvent& event) OVERRIDE;
   virtual bool OnMouseDragged(const MouseEvent& event) OVERRIDE;
-  virtual void OnMouseReleased(const MouseEvent& event, bool canceled) OVERRIDE;
+  virtual void OnMouseReleased(const MouseEvent& event) OVERRIDE;
+  // Showing the drop down results in a MouseCaptureLost, we need to ignore it.
+  virtual void OnMouseCaptureLost() OVERRIDE {}
   virtual void OnMouseExited(const MouseEvent& event) OVERRIDE;
   // Display the right-click menu, as triggered by the keyboard, for instance.
   // Using the member function ShowDropDownMenu for the actual display.