Changes to enable HTML5 autoplay for voice search.

chrome/browser/android/voice_search_tab_helper.cc

+// Copyright 2013 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 "chrome/browser/google/google_util.h"
+#include "content/public/browser/render_view_host.h"
+#include "content/public/browser/web_contents.h"
+#include "jni/VoiceSearchTabHelper_jni.h"
+#include "webkit/common/webpreferences.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();
+  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);
+}