Fix wheel event dispatch logic to fallback to document when hit-test fails

Source/core/input/EventHandler.cpp

 /*
  * Copyright (C) 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc. All rights reserved.
  * Copyright (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2012 Digia Plc. and/or its subsidiary(-ies)
  *
  * 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 1707 matching lines @@
         return false;
 
     RefPtrWillBeRawPtr<FrameView> protector(m_frame->view());
 
     FrameView* view = m_frame->view();
     if (!view)
         return false;
 
     LayoutPoint vPoint = view->rootFrameToContents(event.position());
 
-    HitTestRequest request(HitTestRequest::ReadOnly);
+    // Pass Active to ensure that hit-test result in current document if otherwise empty
+    // TODO(majidvp): Avoid using Active to trigger hit-testing fallback. See http://crbug.com/505825
+    HitTestRequest request(HitTestRequest::ReadOnly | HitTestRequest::Active);
     HitTestResult result(request, vPoint);
     doc->layoutView()->hitTest(result);
 
     Node* node = result.innerNode();
     // Wheel events should not dispatch to text nodes.
     if (node && node->isTextNode())
         node = ComposedTreeTraversal::parent(*node);
 
     bool isOverWidget;
     if (event.useLatchedEventNode()) {
@@ skipping 2022 matching lines @@
 unsigned EventHandler::accessKeyModifiers()
 {
 #if OS(MACOSX)
     return PlatformEvent::CtrlKey | PlatformEvent::AltKey;
 #else
     return PlatformEvent::AltKey;
 #endif
 }
 
 } // namespace blink