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;
+    ASSERT(m_webMediaSession);
 }
 
-void MediaSession::activate()
+MediaSession* MediaSession::create(ExecutionContext* context, ExceptionState& exceptionState)
 {
+    Document* document = toDocument(context);
+    LocalFrame* frame = document->frame();
+    FrameLoaderClient* client = frame->loader().client();
+    OwnPtr<WebMediaSession> webMediaSession = client->createWebMediaSession();
+    if (!webMediaSession) {
+        exceptionState.throwDOMException(NotSupportedError, "Missing platform implementation.");
+        return nullptr;

[mlamouri (slow - plz ping), 2015/10/09 13:01:28]

I'm sceptical of that change. It means that if we tell websites to try the
feature, on Desktop the call te |var session = new MediaSession()| will throw.
That will break their JS code. I will not block the CL on that but please,
consider this.

[philipj_slow, 2015/10/09 15:05:39]

Neither this nor rejecting in activate() and deactivate() as before is something
that could actually be shipped, as neither failure mode is per spec. Until we
can assert that we have a backend, a single point of failure seems nice.

+    }
+    return new MediaSession(webMediaSession.release());
 }
 
-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();
+
+    m_webMediaSession->activate(new CallbackPromiseAdapter<void, MediaSessionError>(resolver));
+    return promise;
+}
+
+ScriptPromise MediaSession::deactivate(ScriptState* scriptState)
+{
+    ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
+    ScriptPromise promise = resolver->promise();
+
+    m_webMediaSession->deactivate(new CallbackPromiseAdapter<void, MediaSessionError>(resolver));
+    return promise;
 }
 
 } // namespace blink