Canvas2d: fix event.region being null on mouseleave/out events

third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp

 /*
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 1108 matching lines @@
     return false;
 }
 
 std::pair<Element*, String> HTMLCanvasElement::getControlAndIdIfHitRegionExists(const LayoutPoint& location)
 {
     if (m_context && m_context->is2d())
         return m_context->getControlAndIdIfHitRegionExists(location);
     return std::make_pair(nullptr, String());
 }
 
+String HTMLCanvasElement::getIdFromControl(const Element* element)
+{
+    if (m_context)
+        return m_context->getIdFromControl(element);
+    return String();
+}
+
 } // namespace blink