Fix bug where constants were not correctly canonicalized.

lib/compiler/implementation/emitter.dart

 // 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.
 
 /**
  * A function element that represents a closure call. The signature is copied
  * from the given element.
  */
 class ClosureInvocationElement extends FunctionElement {
   ClosureInvocationElement(SourceString name,
@@ skipping 129 matching lines @@
         } else {
           Constant value = handler.initialVariableValues[element];
           if (value == null) {
             argumentsBuffer[count] = '(void 0)';
           } else {
             if (!value.isNull()) {
               // If the value is the null constant, we should not pass it
               // down to the native method.
               indexOfLastOptionalArgumentInParameters = count;
             }
-            argumentsBuffer[count] =
-                handler.writeJsCode(new StringBuffer(), value).toString();
+            StringBuffer argumentBuffer = new StringBuffer();
+            handler.writeConstant(argumentBuffer, value);
+            argumentsBuffer[count] = argumentBuffer.toString();
           }
         }
       }
       count++;
     });
     String parametersString = Strings.join(parametersBuffer, ",");
     buffer.add('$parametersString) {\n');
 
     if (isNative) {
       nativeEmitter.emitParameterStub(
@@ skipping 559 matching lines @@
       nativeEmitter.emitDynamicDispatchMetadata();
       mainBuffer.add(
           'var ${namer.CURRENT_ISOLATE} = new ${namer.ISOLATE}();\n');
       nativeEmitter.assembleCode(mainBuffer);
       emitMain(mainBuffer);
       compiler.assembledCode = mainBuffer.toString();
     });
     return compiler.assembledCode;
   }
 }