Implement setSinkId() for media elements without src.

third_party/WebKit/public/web/WebFrameClient.h

 /*
  * Copyright (C) 2011, 2012 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 30 matching lines @@
 #include "WebIconURL.h"
 #include "WebNavigationPolicy.h"
 #include "WebNavigationType.h"
 #include "WebNavigatorContentUtilsClient.h"
 #include "WebSandboxFlags.h"
 #include "WebTextDirection.h"
 #include "public/platform/WebCommon.h"
 #include "public/platform/WebFileSystem.h"
 #include "public/platform/WebFileSystemType.h"
 #include "public/platform/WebSecurityOrigin.h"
+#include "public/platform/WebSetSinkIdCallbacks.h"
 #include "public/platform/WebStorageQuotaCallbacks.h"
 #include "public/platform/WebStorageQuotaType.h"
 #include "public/platform/WebURLError.h"
 #include "public/platform/WebURLRequest.h"
 #include <v8.h>
 
 namespace blink {
 
 enum class WebTreeScopeType;
 class WebApplicationCacheHost;
@@ skipping 606 matching lines @@
     {
         return WebCustomHandlersNew;
     }
 
     // Bluetooth -----------------------------------------------------------
     virtual WebBluetooth* bluetooth() { return 0; }
 
     // WebUSB --------------------------------------------------------------
     virtual WebUSBClient* usbClient() { return nullptr; }
 
+
+    // Audio Output Devices API --------------------------------------------
+
+    // Checks that the given audio sink exists and is authorized. The result is provided via the callback.
+    virtual void checkIfAudioSinkExistsAndIsAuthorized(const WebString& sinkId, const WebSecurityOrigin&, WebSetSinkIdCallbacks*) { }

[Peter Beverloo, 2015/11/09 20:05:06]

nit: document that ownership of |callbacks| is passed.

Not having an implementation of this method means that we'd leak the callbacks.
Can we BLINK_ASSERT_NOT_REACHED() in the default implementation's body?

[Guido Urdaneta, 2015/11/10 15:36:51]

Done.

+
 protected:
     virtual ~WebFrameClient() { }
 };
 
 } // namespace blink
 
 #endif