Put constants in 'C', not '$'.

dart/sdk/lib/_internal/compiler/implementation/js_backend/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.
 
 part of js_backend;
 
 /**
  * A function element that represents a closure call. The signature is copied
  * from the given element.
  */
@@ skipping 861 matching lines @@
       // for (var staticName in isolateProperties) {
       js.forIn('staticName', 'isolateProperties', [
         js.if_('hasOwnProperty.call(isolateProperties, staticName)', [
           js('str += ("this." + staticName + "= properties." + staticName + '
                           '";\\n")')
         ])
       ]),
 
       js('str += "}\\n"'),
 
+      js('var Constants = #', js.fun('', [])),
+      // Install 'C' as a prototype to ensure it has a hidden class.
+      js('Constants.prototype = ${namer.globalObjectForConstant(null)}'),
+
       js('var newIsolate = new Function(str)'),
       js('newIsolate.prototype = isolatePrototype'),
       js('isolatePrototype.constructor = newIsolate'),
       js('newIsolate.${namer.isolatePropertiesName} = isolateProperties'),
       // TODO(ahe): Only copy makeConstantList when it is used.
       js('newIsolate.makeConstantList = oldIsolate.makeConstantList'),
     ]..addAll(copyFinishClasses)
      ..addAll([
 
       // return newIsolate;
@@ skipping 1784 matching lines @@
   jsAst.Expression buildLazyInitializedGetter(VariableElement element) {
     // Nothing to do, the 'lazy' function will create the getter.
     return null;
   }
 
   void emitCompileTimeConstants(CodeBuffer eagerBuffer) {
     ConstantHandler handler = compiler.constantHandler;
     List<Constant> constants = handler.getConstantsForEmission(
         compareConstants);
     bool addedMakeConstantList = false;
+    eagerBuffer.write('var ${namer.globalObjectForConstant(null)}$_=$_{}$N');
     for (Constant constant in constants) {
       if (isConstantInlinedOrAlreadyEmitted(constant)) continue;
       String name = namer.constantName(constant);
       if (!addedMakeConstantList && constant.isList()) {
         addedMakeConstantList = true;
         emitMakeConstantList(eagerBuffer);
       }
       CodeBuffer buffer = bufferForConstant(constant, eagerBuffer);
-      jsAst.Expression init = js('$isolateProperties.$name = #',
+      jsAst.Expression init = js(
+          '${namer.globalObjectForConstant(constant)}.$name = #',
           constantInitializerExpression(constant));
       buffer.write(jsAst.prettyPrint(init, compiler));
       buffer.write('$N');
     }
   }
 
   bool isConstantInlinedOrAlreadyEmitted(Constant constant) {
     if (constant.isFunction()) return true;   // Already emitted.
     if (constant.isPrimitive()) return true;  // Inlined.
     // The name is null when the constant is already a JS constant.
@@ skipping 1359 matching lines @@
 
 const String HOOKS_API_USAGE = """
 // The code supports the following hooks:
 // dartPrint(message)   - if this function is defined it is called
 //                        instead of the Dart [print] method.
 // dartMainRunner(main) - if this function is defined, the Dart [main]
 //                        method will not be invoked directly.
 //                        Instead, a closure that will invoke [main] is
 //                        passed to [dartMainRunner].
 """;