Selectively disable rubber banding on mac.

Source/web/WebInputEvent.cpp

 /*
  * Copyright (C) 2009 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 34 matching lines @@
 
 struct SameSizeAsWebKeyboardEvent : public SameSizeAsWebInputEvent {
     int keyboardData[12];
 };
 
 struct SameSizeAsWebMouseEvent : public SameSizeAsWebInputEvent {
     int mouseData[10];
 };
 
 struct SameSizeAsWebMouseWheelEvent : public SameSizeAsWebMouseEvent {
-    int mousewheelData[10];
+    int mousewheelData[12];
 };
 
 struct SameSizeAsWebGestureEvent : public SameSizeAsWebInputEvent {
     int gestureData[9];
 };
 
 struct SameSizeAsWebTouchEvent : public SameSizeAsWebInputEvent {
     WebTouchPoint touchPoints[3 * WebTouchEvent::touchesLengthCap];
     int touchData[3];
 };
@@ skipping 163 matching lines @@
     case VK_RSHIFT:
     case VK_RMENU:
     case VK_RWIN:
         return IsRight;
     default:
         return 0;
     }
 }
 
 } // namespace blink