Added some basic WebVR use counters

third_party/WebKit/Source/modules/vr/VRDisplay.cpp

Index: third_party/WebKit/Source/modules/vr/VRDisplay.cpp
diff --git a/third_party/WebKit/Source/modules/vr/VRDisplay.cpp b/third_party/WebKit/Source/modules/vr/VRDisplay.cpp
index 0e5f5abd06ad0e28605ee1b4dd45c475140adf71..62d6d4260614e4a8f3349bb4d9c769756304964a 100644
--- a/third_party/WebKit/Source/modules/vr/VRDisplay.cpp
+++ b/third_party/WebKit/Source/modules/vr/VRDisplay.cpp
@@ -6,6 +6,7 @@
 
 #include "core/dom/DOMException.h"
 #include "core/dom/Fullscreen.h"
+#include "core/frame/UseCounter.h"
 #include "core/inspector/ConsoleMessage.h"
 #include "modules/vr/NavigatorVR.h"
 #include "modules/vr/VRController.h"
@@ -97,6 +98,10 @@ bool VRDisplay::getFrameData(VRFrameData* frameData)
 
 VRPose* VRDisplay::getPose()
 {
+    Document* document = m_navigatorVR->document();
+    if (document)
+        UseCounter::count(*document, UseCounter::VRDeprecatedGetPose);
+
     updatePose();
 
     if (!m_framePose)
@@ -255,6 +260,10 @@ void VRDisplay::beginPresent(ScriptPromiseResolver* resolver)
 
     updateLayerBounds();
 
+    Document* document = m_navigatorVR->document();
+    if (document)
+        UseCounter::count(*document, UseCounter::VRPresent);
+
     resolver->resolve();
     m_navigatorVR->fireVRDisplayPresentChange(this);
 }