Make new audionode names backwards compatible.

lib/html/templates/html/impl/impl_AudioContext.darttemplate

Index: lib/html/templates/html/impl/impl_AudioContext.darttemplate
===================================================================
--- lib/html/templates/html/impl/impl_AudioContext.darttemplate	(revision 0)
+++ lib/html/templates/html/impl/impl_AudioContext.darttemplate	(working copy)
@@ -0,0 +1,41 @@
+// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
+// for details. All rights reserved. Use of this source code is governed by a
+// BSD-style license that can be found in the LICENSE file.
+
+class $CLASSNAME$EXTENDS$IMPLEMENTS$NATIVESPEC {
+$!MEMBERS
+$if DART2JS
+  void createGain() {

[sra1, 2012/11/01 20:59:40]

not 'void'.  GainNode?

+    if (JS('bool', '#.createGain !== undefined', this)) {
+      return JS('void', '#.createGain()', this);

[sra1, 2012/11/01 20:59:40]

Ditto about void.

+    } else {
+      return JS('void', '#.createGainNode()', this);
+    }
+  }
+
+  void createScriptProcessor(int bufferSize, [int numberOfInputChannels, int
+      numberOfOutputChannels]) {

[Emily Fortuna, 2012/11/01 18:38:58]

One would think there would be a more concise way to write this logic. But
apparently not. :-(

[sra1, 2012/11/01 20:59:40]

In JS, you can replace
  x.foo(y);
with
  var m = x.foo;
  m.call(x, y);
(i.e. the receiver appears twice)

This will help reduce the code duplication:

var method = JS('dynamic', '#.createScriptProcessor || #.createJavaScriptNode',
this, this);

if (?...) {
  return JS('GainNode', '#.call(#, #, #, E)', method, this,
            bufferSize, numberOfInputChannels, numberOfOutputChannels);

+    if (JS('bool', '#.createScriptProcessor !== undefined', this)) {
+      if (?numberOfOutputChannels) {
+        return JS('void', '#.createScriptProcessor(#, #, #)', this, bufferSize,
+            numberOfInputChannels, numberOfOutputChannels);
+      } else if (?numberOfInputChannels) {
+        return JS('void', '#.createScriptProcessor(#, #)', this, bufferSize,
+            numberOfInputChannels);
+      } else {
+        return JS('void', '#.createScriptProcessor(#)', this, bufferSize);
+      }
+    } else {
+      if (?numberOfOutputChannels) {
+        return JS('void', '#.createJavaScriptNode(#, #, #)', this, bufferSize,
+            numberOfInputChannels, numberOfOutputChannels);
+      } else if (?numberOfInputChannels) {
+        return JS('void', '#.createJavaScriptNode(#, #)', this, bufferSize,
+            numberOfInputChannels);
+      } else {
+        return JS('void', '#.createJavaScriptNode(#)', this, bufferSize);
+      }
+    }
+  }
+$endif
+}