Make reduction value of dynamics compressor zero when no sources are connected

Source/modules/webaudio/AudioNode.h

Index: Source/modules/webaudio/AudioNode.h
diff --git a/Source/modules/webaudio/AudioNode.h b/Source/modules/webaudio/AudioNode.h
index 91d368353e26ed52ef03b2f56d4b0dbfb02eae97..7c80fb1864ecba2a1350eb77059e7a7791f74878 100644
--- a/Source/modules/webaudio/AudioNode.h
+++ b/Source/modules/webaudio/AudioNode.h
@@ -120,6 +120,10 @@ public:
     virtual void initialize();
     virtual void uninitialize();
 
+    // Clear internal state when the node is deactivated. This prevents the node
+    // from providing the incorrect data based on the last-known data inside.

[Raymond Toy, 2014/10/21 20:47:57]

"deactivated" -> "disabled". I think this comment is not quite right. Perhaps
something like:

Clear internal state when the node is disabled.  When a node is disabled, it is
no longer pulled so any internal state is never updated. But some nodes
(DynamicsCompressorNode) have internal state that is still accessible by the
user.  Update the internal state as if the node were still connected but
processing all zeroes. This gives a consistent view to the user.

[hongchan, 2014/10/21 20:58:54]

Acknowledged and replaced.

+    virtual void clearInternalState();

[Raymond Toy, 2014/10/21 20:47:57]

If the comment above is used, perhaps this function should be called
updateInternalStateWhenDisabled instead of clearInternalState?

[hongchan, 2014/10/21 20:58:54]

Good to be more descriptive. But I think this method can be used in other places
where require the reset the internal state. updateInternalState() should be
okay. What do you think?

[Raymond Toy, 2014/10/21 21:05:54]

Hard to say what the future holds. Ok for now, as long as we are careful not to
overuse this to clear internal state.  The comment, however, makes it clear what
this method is supposed to do and when.

+
     bool isInitialized() const { return m_isInitialized; }
 
     unsigned numberOfInputs() const { return m_inputs.size(); }