Added some basic WebVR use counters

third_party/WebKit/Source/modules/vr/NavigatorVR.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 "modules/vr/NavigatorVR.h"
 
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "core/dom/DOMException.h"
 #include "core/dom/Document.h"
 #include "core/dom/ExceptionCode.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "core/frame/LocalFrame.h"
 #include "core/frame/Navigator.h"
+#include "core/frame/UseCounter.h"
 #include "core/page/Page.h"
 #include "modules/vr/VRController.h"
 #include "modules/vr/VRDisplay.h"
 #include "modules/vr/VRGetDevicesCallback.h"
 #include "modules/vr/VRPose.h"
 #include "wtf/PtrUtil.h"
 
 namespace blink {
 
 NavigatorVR* NavigatorVR::from(Document& document)
@@ skipping 25 matching lines @@
     ScriptPromise promise = resolver->promise();
 
     Document* document = m_frame ? m_frame->document() : 0;
 
     if (!document || !controller()) {
         DOMException* exception = DOMException::create(InvalidStateError, "The object is no longer associated to a document.");
         resolver->reject(exception);
         return promise;
     }
 
+    UseCounter::count(*document, UseCounter::VRGetDisplays);
+
     controller()->getDisplays(resolver);
 
     return promise;
 }
 
 VRController* NavigatorVR::controller()
 {
     if (!frame())
         return 0;
 
@@ skipping 33 matching lines @@
 
 void NavigatorVR::fireVRDisplayPresentChange(VRDisplay* display)
 {
     if (m_frame && m_frame->localDOMWindow()) {
         m_frame->localDOMWindow()->enqueueWindowEvent(
             VRDisplayEvent::create(EventTypeNames::vrdisplaypresentchange, true, false, display, ""));
     }
 }
 
 } // namespace blink