Implement setSinkId() for media elements without src.

third_party/WebKit/Source/modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.cpp

Index: third_party/WebKit/Source/modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.cpp
diff --git a/third_party/WebKit/Source/modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.cpp b/third_party/WebKit/Source/modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.cpp
index 930dc3c40b88e366c893b33e4f2691cb812f706b..e78421d2cda860562f68625bab49648e57a09deb 100644
--- a/third_party/WebKit/Source/modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.cpp
+++ b/third_party/WebKit/Source/modules/audio_output_devices/HTMLMediaElementAudioOutputDevice.cpp
@@ -8,6 +8,7 @@
 #include "bindings/core/v8/ScriptPromiseResolver.h"
 #include "bindings/core/v8/ScriptState.h"
 #include "core/dom/ExecutionContext.h"
+#include "modules/audio_output_devices/AudioOutputDeviceClient.h"
 #include "modules/audio_output_devices/SetSinkIdCallbacks.h"
 #include "public/platform/WebSecurityOrigin.h"
 
@@ -34,14 +35,25 @@ ScriptPromise HTMLMediaElementAudioOutputDevice::setSinkId(ScriptState* scriptSt
     ASSERT(scriptState);

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

note: We seem to be missing step 1 of the algorithm here.

1. If sinkId and the sinkId attribute are the same object, return a
   resolved promise. (http://www.w3.org/TR/audio-output/#methods)

|sinkId| is defined to be the empty string as the default value, so most of the
cases in the layout test (lines 24, 30, 50, 52, 63 and 66) would actually hit
this step.

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

Done.

 
     WebMediaPlayer* webMediaPlayer = element.webMediaPlayer();
-    if (!webMediaPlayer)
-        return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(AbortError, "No media player available"));
-
+    ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
+    OwnPtr<SetSinkIdCallbacks> callbacks = adoptPtr(new SetSinkIdCallbacks(resolver, element, sinkId));
     ExecutionContext* context = scriptState->executionContext();
     ASSERT(context && context->isDocument());
 
-    ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
-    webMediaPlayer->setSinkId(sinkId, WebSecurityOrigin(context->securityOrigin()), new SetSinkIdCallbacks(resolver, element, sinkId));
+    if (webMediaPlayer) {
+        // Using leakPtr() to transfer ownership because |webMediaPlayer| is a platform object that takes raw pointers
+        webMediaPlayer->setSinkId(sinkId, WebSecurityOrigin(context->securityOrigin()), callbacks.leakPtr());
+    } else {
+        if (AudioOutputDeviceClient* client = AudioOutputDeviceClient::from(context)) {
+            client->checkIfAudioSinkExistsAndIsAuthorized(context, sinkId, callbacks.release());
+        } else {
+            // The context has been detached. Impossible to get a security origin to check.
+            ASSERT(context->activeDOMObjectsAreStopped());
+            resolver->reject();

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

nit: why not reject the resolver with the dom error? Then you can just
fall-through to the return on line 57.

resolver->reject(DOMException::create(SecurityError, "Impossible to authorize
device for detached context"));

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

Done. Note that the implementation is slightly different now as it is
asynchronous in Blink.

+            return ScriptPromise::rejectWithDOMException(scriptState,  DOMException::create(SecurityError, "Impossible to authorize device for detached context"));
+        }
+    }
+
     return resolver->promise();
 }