Lazy initialization of the rendering thread in OfflineAudioContext

third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.cpp

Index: third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.cpp
diff --git a/third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.cpp b/third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.cpp
index 1b310a9db147308bf597838d58b70511ed36e1ad..39eb1427f2d806d7cf3f03c42116a47cd8121ae3 100644
--- a/third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.cpp
+++ b/third_party/WebKit/Source/modules/webaudio/OfflineAudioContext.cpp
@@ -230,13 +230,6 @@ ScriptPromise OfflineAudioContext::suspendContext(ScriptState* script_state,
   ScriptPromiseResolver* resolver = ScriptPromiseResolver::Create(script_state);
   ScriptPromise promise = resolver->Promise();
 
-  // The render thread does not exist; reject the promise.
-  if (!DestinationHandler().OfflineRenderThread()) {
-    resolver->Reject(DOMException::Create(kInvalidStateError,
-                                          "the rendering is already finished"));
-    return promise;
-  }
-

[hongchan, 2017/05/19 17:35:06]

The existence of thread and being able to schedule a context suspend are
orthogonal. Not sure why this code was here in the first place.

WDYT?

[Raymond Toy, 2017/05/19 19:37:54]

Based on the comments, when rendering is done, the thread goes away, and we're
rejecting because you can't suspend a context that as already finished
rendering.

If that's correct, can you check if we have a test for this?  If we don't we
probably should.

   // The specified suspend time is negative; reject the promise.
   if (when < 0) {
     resolver->Reject(DOMException::Create(