Implementation of setSinkId() for HTMLMediaElement.

Source/modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.cpp

 // Copyright 2015 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 "config.h"
 #include "modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.h"
 
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "core/dom/ExecutionContext.h"
+#include "modules/audio_output_devices/SetSinkIdCallbacks.h"
 #include "platform/Logging.h"
 
 namespace blink {
 
 HTMLMediaElementAudioOutputDevice::HTMLMediaElementAudioOutputDevice()
     : m_sinkId("")
 {
 }
 
 String HTMLMediaElementAudioOutputDevice::sinkId(HTMLMediaElement& element)
 {
     WTF_LOG(Media, __FUNCTION__);
     HTMLMediaElementAudioOutputDevice& aodElement = HTMLMediaElementAudioOutputDevice::from(element);
     return aodElement.m_sinkId;
 }
 
-ScriptPromise HTMLMediaElementAudioOutputDevice::setSinkId(ScriptState* scriptState, HTMLMediaElement& element, const String& newSinkId)
+void HTMLMediaElementAudioOutputDevice::setSinkId(const String& sinkId)
+{
+    m_sinkId = sinkId;
+}
+
+ScriptPromise HTMLMediaElementAudioOutputDevice::setSinkId(ScriptState* scriptState, HTMLMediaElement& element, const String& sinkId)
 {
     WTF_LOG(Media, __FUNCTION__);
-    return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(NotSupportedError, "Operation not supported"));
+    WebMediaPlayer* webMediaPlayer = element.webMediaPlayer();
+    if (!webMediaPlayer)
+        return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(AbortError, "No media player available"));

[Peter Beverloo, 2015/06/18 14:33:15]

As in the other CL - should this be an ASSERT()?

[Guido Urdaneta, 2015/06/18 23:09:05]

In this case the check is valid.
For empty media elements (e.g.g <video id="empty"></video>, webMediaPlayer is
actually null, and in that case there is no actual audio sink to be set.

The spec needs some updates because it says that in these cases a rejected
promise should be returned, but it does not specify with what kind of exception.


I asked hta, who is involved in spec writing, and he told me that, until the
specification is clearer, AbortError is a good error to use.

+
+    RefPtrWillBeRawPtr<ScriptPromiseResolver> resolver = ScriptPromiseResolver::create(scriptState);
+    HTMLMediaElementAudioOutputDevice& aodElement = HTMLMediaElementAudioOutputDevice::from(element);
+    if (sinkId == aodElement.m_sinkId)
+        resolver->resolve();
+    else
+        webMediaPlayer->setSinkId(sinkId, new SetSinkIdCallbacks(resolver, element, sinkId));
+
+    return resolver->promise();
 }
 
 const char* HTMLMediaElementAudioOutputDevice::supplementName()
 {
     return "HTMLMediaElementAudioOutputDevice";
 }
 
 HTMLMediaElementAudioOutputDevice& HTMLMediaElementAudioOutputDevice::from(HTMLMediaElement& element)
 {
     HTMLMediaElementAudioOutputDevice* supplement = static_cast<HTMLMediaElementAudioOutputDevice*>(WillBeHeapSupplement<HTMLMediaElement>::from(element, supplementName()));
     if (!supplement) {
         supplement = new HTMLMediaElementAudioOutputDevice();
         provideTo(element, supplementName(), adoptPtrWillBeNoop(supplement));
     }
     return *supplement;
 }
 
 DEFINE_TRACE(HTMLMediaElementAudioOutputDevice)
 {
     WillBeHeapSupplement<HTMLMediaElement>::trace(visitor);
 }
 
 } // namespace blink