Add UseCounters for navigator.vibrate usage compared to site engagement.

third_party/WebKit/Source/modules/vibration/NavigatorVibration.cpp

Index: third_party/WebKit/Source/modules/vibration/NavigatorVibration.cpp
diff --git a/third_party/WebKit/Source/modules/vibration/NavigatorVibration.cpp b/third_party/WebKit/Source/modules/vibration/NavigatorVibration.cpp
index 95e5b353ce92c7bb4da370d38504a524671702ad..2e82f6fc650068f71f2a4a278411932011c458c0 100644
--- a/third_party/WebKit/Source/modules/vibration/NavigatorVibration.cpp
+++ b/third_party/WebKit/Source/modules/vibration/NavigatorVibration.cpp
@@ -29,6 +29,7 @@
 #include "modules/vibration/VibrationController.h"
 #include "platform/Histogram.h"
 #include "platform/UserGestureIndicator.h"
+#include "public/platform/site_engagement.mojom-blink.h"
 
 namespace blink {
 
@@ -124,6 +125,22 @@ void NavigatorVibration::collectHistogramMetrics(const LocalFrame& frame) {
   DEFINE_STATIC_LOCAL(EnumerationHistogram, NavigatorVibrateHistogram,
                       ("Vibration.Context", NavigatorVibrationType::EnumMax));
   NavigatorVibrateHistogram.count(type);
+
+  mojom::blink::EngagementLevel level = frame.document()->getEngagementLevel();
+  if (level == mojom::blink::EngagementLevel::NONE)

[haraken, 2017/01/06 00:56:27]

Shall we use a switch statement?

[dominickn, 2017/01/06 01:38:34]

Done - though it's a bit more verbose as a result.

+    UseCounter::count(&frame, UseCounter::NavigatorVibrateEngagementNone);
+  else if (level == mojom::blink::EngagementLevel::MINIMAL)
+    UseCounter::count(&frame, UseCounter::NavigatorVibrateEngagementMinimal);
+  else if (level == mojom::blink::EngagementLevel::LOW)
+    UseCounter::count(&frame, UseCounter::NavigatorVibrateEngagementLow);
+  else if (level == mojom::blink::EngagementLevel::MEDIUM)
+    UseCounter::count(&frame, UseCounter::NavigatorVibrateEngagementMedium);
+  else if (level == mojom::blink::EngagementLevel::HIGH)
+    UseCounter::count(&frame, UseCounter::NavigatorVibrateEngagementHigh);
+  else if (level == mojom::blink::EngagementLevel::MAX)
+    UseCounter::count(&frame, UseCounter::NavigatorVibrateEngagementMax);
+  else
+    NOTREACHED();
 }
 
 VibrationController* NavigatorVibration::controller(const LocalFrame& frame) {