[Media Controls] Add UMA for rotate-to-fullscreen feature

third_party/WebKit/Source/modules/media_controls/MediaControlsRotateToFullscreenDelegate.cpp

 // Copyright 2017 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/media_controls/MediaControlsRotateToFullscreenDelegate.h"
 
 #include "core/dom/ElementVisibilityObserver.h"
 #include "core/dom/Fullscreen.h"
 #include "core/dom/UserGestureIndicator.h"
 #include "core/events/Event.h"
 #include "core/frame/LocalDOMWindow.h"
 #include "core/html/HTMLVideoElement.h"
 #include "core/page/ChromeClient.h"
 #include "modules/media_controls/MediaControlsImpl.h"
+#include "public/platform/Platform.h"
 #include "public/platform/WebScreenInfo.h"
 
 namespace blink {
 
 namespace {
 
 // Videos must be at least this big in both dimensions to qualify.
 constexpr unsigned kMinSize = 200;
 
 // At least this fraction of the video must be visible.
@@ skipping 147 matching lines @@
 
   MediaControlsImpl& media_controls =
       *static_cast<MediaControlsImpl*>(video_element_->GetMediaControls());
 
   {
     UserGestureIndicator gesture(
         UserGestureToken::Create(&video_element_->GetDocument()));
 
     bool should_be_fullscreen =
         current_screen_orientation_ == video_orientation;
-    if (should_be_fullscreen && !video_element_->IsFullscreen())
+    if (should_be_fullscreen && !video_element_->IsFullscreen()) {
+      Platform::Current()->RecordAction(
+          UserMetricsAction("Media.Video.RotateToFullscreen.Enter"));
       media_controls.EnterFullscreen();
-    else if (!should_be_fullscreen && video_element_->IsFullscreen())
+    } else if (!should_be_fullscreen && video_element_->IsFullscreen()) {
+      Platform::Current()->RecordAction(
+          UserMetricsAction("Media.Video.RotateToFullscreen.Exit"));
       media_controls.ExitFullscreen();
+    }
   }
 }
 
 MediaControlsRotateToFullscreenDelegate::SimpleOrientation
 MediaControlsRotateToFullscreenDelegate::ComputeVideoOrientation() const {
   if (video_element_->getReadyState() == HTMLMediaElement::kHaveNothing)
     return SimpleOrientation::kUnknown;
 
   const unsigned width = video_element_->videoWidth();
   const unsigned height = video_element_->videoHeight();
@@ skipping 27 matching lines @@
   return SimpleOrientation::kUnknown;
 }
 
 DEFINE_TRACE(MediaControlsRotateToFullscreenDelegate) {
   EventListener::Trace(visitor);
   visitor->Trace(video_element_);
   visitor->Trace(visibility_observer_);
 }
 
 }  // namespace blink