Introduce WebMediaSession

third_party/WebKit/Source/modules/mediasession/MediaSession.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/mediasession/MediaSession.h"
 
+#include "bindings/core/v8/CallbackPromiseAdapter.h"
+#include "bindings/core/v8/ScriptPromiseResolver.h"
+#include "bindings/core/v8/ScriptState.h"
+#include "core/dom/DOMException.h"
+#include "core/dom/ExceptionCode.h"
+#include "core/frame/LocalDOMWindow.h"
+#include "core/frame/LocalFrame.h"
+#include "core/loader/FrameLoaderClient.h"
+#include "modules/mediasession/MediaSessionError.h"
+
 namespace blink {
 
-MediaSession* MediaSession::create()
+MediaSession::MediaSession(PassOwnPtr<WebMediaSession> webMediaSession)
+    : m_webMediaSession(webMediaSession)
 {
-    return new MediaSession;
+#if OS(ANDROID)
+    ASSERT(m_webMediaSession);
+#else
+    ASSERT(!m_webMediaSession);
+#endif // ANDROID
 }
 
-void MediaSession::activate()
+MediaSession* MediaSession::create(ExecutionContext* context)
 {
+    Document* document = toDocument(context);
+    LocalFrame* frame = document->frame();
+    FrameLoaderClient* client = frame->loader().client();
+    return new MediaSession(client->createWebMediaSession());

[philipj_slow, 2015/10/07 14:37:12]

If we throw an exception when client->createWebMediaSession() returns nullptr,
so that there can be no MediaSession instance without a backend. Now we only
have two places where this is handled, but there may be more.

[davve, 2015/10/08 09:17:35]

Done.

 }
 
-void MediaSession::deactivate()
+MediaSession* MediaSession::createForTesting(PassOwnPtr<WebMediaSession> webMediaSession)
 {
+    return new MediaSession(webMediaSession);
+}
+
+ScriptPromise MediaSession::activate(ScriptState* scriptState)
+{
+    ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
+    ScriptPromise promise = resolver->promise();
+    if (m_webMediaSession)
+        m_webMediaSession->activate(new CallbackPromiseAdapter<void, MediaSessionError>(resolver));
+    else
+        resolver->reject(DOMException::create(NotSupportedError, "Missing platform implementation."));

[mlamouri (slow - plz ping), 2015/10/07 14:19:30]

I would argue that rejecting with DOMException and TypeError is a bit odd but I
guess this DOMException isn't meant to stay forever.

[davve, 2015/10/08 09:17:35]

By moving the exception throwing to the constructor we at least doesn't mix and
match in the same promise.

+    return promise;
+}
+
+ScriptPromise MediaSession::deactivate(ScriptState* scriptState)
+{
+    ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
+    ScriptPromise promise = resolver->promise();
+    if (m_webMediaSession)
+        m_webMediaSession->deactivate(new CallbackPromiseAdapter<void, MediaSessionError>(resolver));
+    else
+        resolver->reject(DOMException::create(NotSupportedError, "Missing platform implementation."));
+    return promise;
 }
 
 } // namespace blink