Defer changes to channelInterpretation to pre/post rendering.

third_party/WebKit/Source/modules/webaudio/AbstractAudioContext.h

Index: third_party/WebKit/Source/modules/webaudio/AbstractAudioContext.h
diff --git a/third_party/WebKit/Source/modules/webaudio/AbstractAudioContext.h b/third_party/WebKit/Source/modules/webaudio/AbstractAudioContext.h
index 53c158fbf02b32cbf9f524272e9b02c81b760289..03410b5aab773e8bea80cd4db4324ff794176575 100644
--- a/third_party/WebKit/Source/modules/webaudio/AbstractAudioContext.h
+++ b/third_party/WebKit/Source/modules/webaudio/AbstractAudioContext.h
@@ -232,10 +232,8 @@ public:
     void lock() { deferredTaskHandler().lock(); }
     bool tryLock() { return deferredTaskHandler().tryLock(); }
     void unlock() { deferredTaskHandler().unlock(); }
-#if ENABLE(ASSERT)
     // Returns true if this thread owns the context's lock.
     bool isGraphOwner() { return deferredTaskHandler().isGraphOwner(); }
-#endif

[hongchan, 2016/05/26 21:00:57]

What is the meaning of this? Perhaps there was a time that ASSERT was used
rarely?

[Raymond Toy, 2016/05/26 21:06:58]

I discovered this just now.  Previously ASSERT(...) would generate no code if
asserts were disabled.  But DCHECK always emits something (so variables in
DCHECK are used), so now we need to have isGraphOwner defined so that DCHECK is
valid.

[Nico, 2016/05/27 13:09:33]

That doesn't sound right. DCHECK() compiles to nothing if dchecks are not
enabled.

     using AutoLocker = DeferredTaskHandler::AutoLocker;
 
     // Returns the maximum numuber of channels we can support.