Fix problem that caused anonymous mixin applications to be named "null".

dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart

Index: dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart
diff --git a/dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart b/dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart
index 5c52a80282486c2729c99232a23d9b20f13c3851..609e97f7a4b07e8decfa9e7da8b72f8c3bf602d1 100644
--- a/dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart
+++ b/dart/sdk/lib/_internal/compiler/implementation/js_backend/emitter.dart
@@ -1986,8 +1986,8 @@ class CodeEmitterTask extends CompilerTask {
     }
     buffer.write('$className:$_');
     buffer.write(jsAst.prettyPrint(builder.toObjectInitializer(), compiler));
-    if (backend.shouldRetainName(classElement.name)) {
-      String reflectionName = getReflectionName(classElement, className);
+    String reflectionName = getReflectionName(classElement, className);

[ngeoffray, 2013/08/16 07:28:34]

The previous version read better. Could you have a higher abstraction than just
doing a null check?

[ahe, 2013/08/16 08:32:29]

Not sure. The problem is that I might also cache stuff in getReflection name, so
even if the backend tells us to retain the name, getReflection might return
null.

For example, I only need to record once that toString$0 is toString:0:0.

Also, you can see getReflectionName is now used consistently throughout the
emitter. 

Cheers,
Peter

+    if (reflectionName != null) {
       List<int> interfaces = <int>[];
       for (DartType interface in classElement.interfaces) {
         interfaces.add(reifyType(interface));