Add UMA metric for tracking listeners for blocking touch while fling is happening

third_party/WebKit/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 41 matching lines @@
 struct SameSizeAsWebMouseWheelEvent : public SameSizeAsWebMouseEvent {
     int mousewheelData[13];
 };
 
 struct SameSizeAsWebGestureEvent : public SameSizeAsWebInputEvent {
     int gestureData[12];
 };
 
 struct SameSizeAsWebTouchEvent : public SameSizeAsWebInputEvent {
     WebTouchPoint touchPoints[WebTouchEvent::touchesLengthCap];
-    int touchData[4];
+    int touchData[5];
 };
 
 static_assert(sizeof(WebInputEvent) == sizeof(SameSizeAsWebInputEvent), "WebInputEvent should not have gaps");
 static_assert(sizeof(WebKeyboardEvent) == sizeof(SameSizeAsWebKeyboardEvent), "WebKeyboardEvent should not have gaps");
 static_assert(sizeof(WebMouseEvent) == sizeof(SameSizeAsWebMouseEvent), "WebMouseEvent should not have gaps");
 static_assert(sizeof(WebMouseWheelEvent) == sizeof(SameSizeAsWebMouseWheelEvent), "WebMouseWheelEvent should not have gaps");
 static_assert(sizeof(WebGestureEvent) == sizeof(SameSizeAsWebGestureEvent), "WebGestureEvent should not have gaps");
 static_assert(sizeof(WebTouchEvent) == sizeof(SameSizeAsWebTouchEvent), "WebTouchEvent should not have gaps");
 
 static const char* staticKeyIdentifiers(unsigned short keyCode)
@@ skipping 118 matching lines @@
 {
     const char* id = staticKeyIdentifiers(windowsKeyCode);
     if (id) {
         strncpy(keyIdentifier, id, sizeof(keyIdentifier) - 1);
         keyIdentifier[sizeof(keyIdentifier) - 1] = '\0';
     } else
         snprintf(keyIdentifier, sizeof(keyIdentifier), "U+%04X", toupper(windowsKeyCode));
 }
 
 } // namespace blink