Bookkeep the pointer event listeners added to page

third_party/WebKit/Source/core/frame/EventHandlerRegistry.h

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef EventHandlerRegistry_h
 #define EventHandlerRegistry_h
 
 #include "core/CoreExport.h"  // TODO(sashab): Remove this.
 #include "core/page/Page.h"
 #include "platform/wtf/HashCountedSet.h"
@@ skipping 19 matching lines @@
   // Supported event handler classes. Note that each one may correspond to
   // multiple event types.
   enum EventHandlerClass {
     kScrollEvent,
     kWheelEventBlocking,
     kWheelEventPassive,
     kTouchStartOrMoveEventBlocking,
     kTouchStartOrMoveEventPassive,
     kTouchEndOrCancelEventBlocking,
     kTouchEndOrCancelEventPassive,
+    kPointerEvent,
 #if DCHECK_IS_ON()
     // Additional event categories for verifying handler tracking logic.
     kEventsForTesting,
 #endif
     kEventHandlerClassCount,  // Must be the last entry.
   };
 
   // Returns true if the Page has event handlers of the specified class.
   bool HasEventHandlers(EventHandlerClass) const;
 
@@ skipping 71 matching lines @@
 
   void CheckConsistency(EventHandlerClass) const;
 
   Member<Page> page_;
   EventTargetSet targets_[kEventHandlerClassCount];
 };
 
 }  // namespace blink
 
 #endif  // EventHandlerRegistry_h