Presentation API: add UMA.

Source/modules/presentation/PresentationRequest.cpp

 // Copyright 2015 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.
 
 #include "config.h"
 #include "modules/presentation/PresentationRequest.h"
 
 #include "bindings/core/v8/CallbackPromiseAdapter.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExecutionContext.h"
+#include "core/frame/UseCounter.h"
 #include "modules/EventTargetModules.h"
 #include "modules/presentation/PresentationAvailability.h"
 #include "modules/presentation/PresentationAvailabilityCallbacks.h"
 #include "modules/presentation/PresentationController.h"
 #include "modules/presentation/PresentationError.h"
 #include "modules/presentation/PresentationSession.h"
 #include "modules/presentation/PresentationSessionCallbacks.h"
 
 namespace blink {
 
@@ skipping 30 matching lines @@
 const AtomicString& PresentationRequest::interfaceName() const
 {
     return EventTargetNames::PresentationRequest;
 }
 
 ExecutionContext* PresentationRequest::executionContext() const
 {
     return ActiveDOMObject::executionContext();
 }
 
+bool PresentationRequest::addEventListener(const AtomicString& eventType, PassRefPtrWillBeRawPtr<EventListener> listener, bool capture)
+{
+    if (eventType == EventTypeNames::sessionconnect)
+        UseCounter::count(executionContext(), UseCounter::PresentationRequestSessionConnectEventListener);
+
+    return EventTarget::addEventListener(eventType, listener, capture);
+}
+
 bool PresentationRequest::hasPendingActivity() const
 {
     // Prevents garbage collecting of this object when not hold by another
     // object but still has listeners registered.
     return hasEventListeners();
 }
 
 ScriptPromise PresentationRequest::start(ScriptState* scriptState)
 {
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
@@ skipping 49 matching lines @@
     ActiveDOMObject::trace(visitor);
 }
 
 PresentationRequest::PresentationRequest(ExecutionContext* executionContext, const KURL& url)
     : ActiveDOMObject(executionContext)
     , m_url(url)
 {
 }
 
 } // namespace blink