Enable user gesture requirement for autoplay experiment.

third_party/WebKit/Source/core/html/AutoplayExperimentHelper.cpp

 // Copyright 2016 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 "core/html/AutoplayExperimentHelper.h"
 
 #include "core/dom/Document.h"
 #include "core/frame/Settings.h"
 #include "core/html/HTMLMediaElement.h"
 #include "core/layout/LayoutBox.h"
@@ skipping 21 matching lines @@
     , m_autoplayMediaEncountered(false)
     , m_playbackStartedMetricRecorded(false)
     , m_waitingForAutoplayPlaybackEnd(false)
     , m_recordedElement(false)
     , m_lastLocationUpdateTime(-std::numeric_limits<double>::infinity())
     , m_viewportTimer(this, &AutoplayExperimentHelper::viewportTimerFired)
     , m_autoplayDeferredMetric(GesturelessPlaybackNotOverridden)
 {
     m_mode = fromString(this->client().autoplayExperimentMode());
 
-    if (m_mode != Mode::ExperimentOff) {
+    if (isExperimentEnabled()) {
         WTF_LOG(Media, "HTMLMediaElement: autoplay experiment set to %d",
             m_mode);
     }
 }
 
 AutoplayExperimentHelper::~AutoplayExperimentHelper()
 {
 }
 
 void AutoplayExperimentHelper::dispose()
@@ skipping 436 matching lines @@
     recordAutoplayMetric(client().isHTMLVideoElement()
         ? AnyVideoElement
         : AnyAudioElement);
 }
 
 bool AutoplayExperimentHelper::requiresViewportVisibility() const
 {
     return enabled(IfViewport) || enabled(IfPartialViewport);
 }
 
+bool AutoplayExperimentHelper::isExperimentEnabled()
+{
+    return m_mode != Mode::ExperimentOff;
+}
+
 } // namespace blink