Implement suspend() and resume() for OfflineAudioContext

Source/modules/webaudio/AudioContext.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/webaudio/AudioContext.h"
 
 #include "bindings/core/v8/ExceptionMessages.h"
 #include "bindings/core/v8/ExceptionState.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
@@ skipping 59 matching lines @@
     fprintf(stderr, "%p: AudioContext::~AudioContext(): %u\n", this, m_contextId);
 #endif
 }
 
 DEFINE_TRACE(AudioContext)
 {
     visitor->trace(m_closeResolver);
     AbstractAudioContext::trace(visitor);
 }
 
+ScriptPromise AudioContext::closeContext(ScriptState* scriptState)
+{
+    if (isContextClosed()) {
+        // We've already closed the context previously, but it hasn't yet been resolved, so just
+        // create a new promise and reject it.
+        return ScriptPromise::rejectWithDOMException(
+            scriptState,
+            DOMException::create(InvalidStateError,
+                "Cannot close a context that is being closed or has already been closed."));
+    }
+
+    m_closeResolver = ScriptPromiseResolver::create(scriptState);
+    ScriptPromise promise = m_closeResolver->promise();
+
+    // Stop the audio context. This will stop the destination node from pulling audio anymore. And
+    // since we have disconnected the destination from the audio graph, and thus has no references,
+    // the destination node can GCed if JS has no references. uninitialize() will also resolve the Promise
+    // created here.
+    uninitialize();
+
+    return promise;

[Raymond Toy, 2015/07/15 20:59:14]

Is there a bug here? I don't think uninitialize() will resolve m_closeResolver,
so where does it get resolved now?

[hongchan, 2015/07/15 23:24:22]

I blindly merged the ToT and change the location. I will look into the issue,
but that should be another CL.

+}
+
 ScriptPromise AudioContext::suspendContext(ScriptState* scriptState)
 {
     ASSERT(isMainThread());
     AutoLocker locker(this);
 
     RefPtrWillBeRawPtr<ScriptPromiseResolver> resolver = ScriptPromiseResolver::create(scriptState);
     ScriptPromise promise = resolver->promise();
 
     if (contextState() == Closed) {
         resolver->reject(
             DOMException::create(InvalidStateError, "Cannot suspend a context that has been closed"));
     } else {
         // Stop rendering now.
         if (destination())
             stopRendering();
 
         // Since we don't have any way of knowing when the hardware actually stops, we'll just
         // resolve the promise now.
         resolver->resolve();
     }
 
     return promise;
 }
 
+ScriptPromise AudioContext::suspendContext(ScriptState* scriptState, double suspendTime)
+{
+    ASSERT_NOT_REACHED();
+}
+
 ScriptPromise AudioContext::resumeContext(ScriptState* scriptState)
 {
     ASSERT(isMainThread());
 
     if (isContextClosed()) {
         return ScriptPromise::rejectWithDOMException(
             scriptState,
             DOMException::create(
                 InvalidAccessError,
                 "cannot resume a closed AudioContext"));
     }
 
     RefPtrWillBeRawPtr<ScriptPromiseResolver> resolver = ScriptPromiseResolver::create(scriptState);
     ScriptPromise promise = resolver->promise();
 
     // Restart the destination node to pull on the audio graph.
     if (destination())
         startRendering();
 
     // Save the resolver which will get resolved when the destination node starts pulling on the
     // graph again.
     {
-        AutoLocker locker(this);
+        AutoLocker(this);
         m_resumeResolvers.append(resolver);
     }
 
     return promise;
 }
 
-ScriptPromise AudioContext::closeContext(ScriptState* scriptState)
-{
-    if (isContextClosed()) {
-        // We've already closed the context previously, but it hasn't yet been resolved, so just
-        // create a new promise and reject it.
-        return ScriptPromise::rejectWithDOMException(
-            scriptState,
-            DOMException::create(InvalidStateError,
-                "Cannot close a context that is being closed or has already been closed."));
-    }
-
-    m_closeResolver = ScriptPromiseResolver::create(scriptState);
-    ScriptPromise promise = m_closeResolver->promise();
-
-    // Stop the audio context. This will stop the destination node from pulling audio anymore. And
-    // since we have disconnected the destination from the audio graph, and thus has no references,
-    // the destination node can GCed if JS has no references. uninitialize() will also resolve the Promise
-    // created here.
-    uninitialize();
-
-    return promise;
-}
-
 void AudioContext::didClose()
 {
     // This is specific to AudioContexts. OfflineAudioContexts
     // are closed in their completion event.
     setContextState(Closed);
 
     ASSERT(s_hardwareContextCount);
     --s_hardwareContextCount;
 
     if (m_closeResolver)
@@ skipping 13 matching lines @@
     if (contextState() == Running) {
         destination()->audioDestinationHandler().stopRendering();
         setContextState(Suspended);
         deferredTaskHandler().clearHandlersToBeDeleted();
     }
 }
 
 } // namespace blink
 
 #endif // ENABLE(WEB_AUDIO)