disable web audio by default on android and add switches to enable it

BUG=
TEST=


Review URL: https://chromiumcodereview.appspot.com/10810034

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@148516 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/renderer_host/render_process_host_impl.cc

@@ -748,7 +748,11 @@ void RenderProcessHostImpl::PropagateBrowserCommandLineToRenderer(
     switches::kDisableSpeechInput,
     switches::kEnableScriptedSpeech,
     switches::kDisableThreadedAnimation,
+#if defined(OS_ANDROID)
+    switches::kEnableWebAudio,
+#else
     switches::kDisableWebAudio,
+#endif
     switches::kDisableWebSockets,
     switches::kDomAutomationController,
     switches::kEnableAccessibilityLogging,

content/browser/web_contents/web_contents_impl.cc

@@ -428,8 +428,13 @@ WebPreferences WebContentsImpl::GetWebkitPrefs(RenderViewHost* rvh,
       !command_line.HasSwitch(switches::kDisableLocalStorage);
   prefs.databases_enabled =
       !command_line.HasSwitch(switches::kDisableDatabases);
+#if defined(OS_ANDROID)
+  prefs.webaudio_enabled =
+      command_line.HasSwitch(switches::kEnableWebAudio);
+#else
   prefs.webaudio_enabled =
       !command_line.HasSwitch(switches::kDisableWebAudio);
+#endif
 
   prefs.experimental_webgl_enabled =
       GpuProcessHost::gpu_enabled() &&

content/public/common/content_switches.cc

@@ -212,8 +212,13 @@ const char kSpeechRecognitionWebserviceKey[] = "speech-service-key";
 // Disables animation on the compositor thread.
 const char kDisableThreadedAnimation[]      = "disable-threaded-animation";
 
+#if defined(OS_ANDROID)
+// Enable web audio API.
+const char kEnableWebAudio[]                = "enable-webaudio";
+#else
 // Disable web audio API.
 const char kDisableWebAudio[]               = "disable-webaudio";
+#endif
 
 // Don't enforce the same-origin policy. (Used by people testing their sites.)
 const char kDisableWebSecurity[]            = "disable-web-security";

content/public/common/content_switches.h

@@ -79,7 +79,11 @@ CONTENT_EXPORT extern const char kEnableScriptedSpeech[];
 extern const char kSpeechRecognitionWebserviceURL[];
 extern const char kSpeechRecognitionWebserviceKey[];
 CONTENT_EXPORT extern const char kDisableThreadedAnimation[];
+#if defined(OS_ANDROID)
+CONTENT_EXPORT extern const char kEnableWebAudio[];
+#else
 CONTENT_EXPORT extern const char kDisableWebAudio[];
+#endif
 extern const char kDisableWebSecurity[];
 extern const char kDisableWebSockets[];
 extern const char kDisableXSSAuditor[];

content/renderer/render_thread_impl.cc

@@ -586,9 +586,15 @@ void RenderThreadImpl::EnsureWebKitInitialized() {
   WebKit::WebRuntimeFeatures::enableEncryptedMedia(
       command_line.HasSwitch(switches::kEnableEncryptedMedia));
 
+#if defined(OS_ANDROID)
+  WebRuntimeFeatures::enableWebAudio(
+      command_line.HasSwitch(switches::kEnableWebAudio) &&
+      media::IsMediaLibraryInitialized());
+#else
   WebRuntimeFeatures::enableWebAudio(
       !command_line.HasSwitch(switches::kDisableWebAudio) &&
       media::IsMediaLibraryInitialized());
+#endif
 
   WebRuntimeFeatures::enablePushState(true);