Add Frame::isMainFrame and deploy it

Source/core/page/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 3790 matching lines @@
     SyntheticSingleTouchEvent touchEvent(event);
     if (handleTouchEvent(touchEvent))
         return true;
 
     return handleMouseEventAsEmulatedGesture(event);
 }
 
 bool EventHandler::handleMouseEventAsEmulatedGesture(const PlatformMouseEvent& event)
 {
     PlatformEvent::Type eventType = event.type();
-    Page* page = m_frame->page();
-    FrameView* view = m_frame->view();
-    if (event.button() != LeftButton || page->mainFrame() != m_frame)
+    if (event.button() != LeftButton || !m_frame->isMainFrame())
         return false;
 
     // Simulate pinch / scroll gesture.
     const IntPoint& position = event.position();
     bool swallowEvent = false;
 
+    FrameView* view = m_frame->view();
     if (event.shiftKey()) {
         // Shift pressed - consider it gesture.
         swallowEvent = true;
+        Page* page = m_frame->page();
         float pageScaleFactor = page->pageScaleFactor();
         switch (eventType) {
         case PlatformEvent::MousePressed:
             m_lastSyntheticPinchAnchorCss = adoptPtr(new IntPoint(view->scrollPosition() + position));
             m_lastSyntheticPinchAnchorDip = adoptPtr(new IntPoint(position));
             m_lastSyntheticPinchAnchorDip->scale(pageScaleFactor, pageScaleFactor);
             m_syntheticPageScaleFactor = pageScaleFactor;
             break;
         case PlatformEvent::MouseMoved:
             {
@@ skipping 144 matching lines @@
 unsigned EventHandler::accessKeyModifiers()
 {
 #if OS(MACOSX)
     return PlatformEvent::CtrlKey | PlatformEvent::AltKey;
 #else
     return PlatformEvent::AltKey;
 #endif
 }
 
 } // namespace WebCore