Enable HTMLMediaElement@autoplay on Android

chrome/browser/android/voice_search_tab_helper.cc

-// Copyright 2014 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 "chrome/browser/android/voice_search_tab_helper.h"
-
-#include "components/google/core/browser/google_util.h"
-#include "content/public/browser/render_view_host.h"
-#include "content/public/browser/web_contents.h"
-#include "content/public/common/web_preferences.h"
-#include "jni/VoiceSearchTabHelper_jni.h"
-
-using content::WebContents;
-
-// Register native methods
-bool RegisterVoiceSearchTabHelper(JNIEnv* env) {
-  return RegisterNativesImpl(env);
-}
-
-static void UpdateAutoplayStatus(JNIEnv* env,
-                                 jobject obj,
-                                 jobject j_web_contents) {
-  WebContents* web_contents = WebContents::FromJavaWebContents(j_web_contents);
-  content::RenderViewHost* host = web_contents->GetRenderViewHost();
-  content::WebPreferences prefs = host->GetWebkitPreferences();
-
-  // In the case where media autoplay has been enabled by default (e.g. in
-  // performance media tests) do not update it based on navigation changes.
-  //
-  // Note that GetWekitPreferences() is 'stateless'. It returns the default
-  // webkit preferences configuration from command line switches.
-  if (!prefs.user_gesture_required_for_media_playback)
-    return;
-
-  prefs.user_gesture_required_for_media_playback =
-      !google_util::IsGoogleSearchUrl(web_contents->GetLastCommittedURL());
-  host->UpdateWebkitPreferences(prefs);
-}