dart2js: Use an abstract Name class for names in the generated JavaScript ast.

pkg/compiler/lib/src/js_emitter/parameter_stub_generator.dart

 // Copyright (c) 2015, 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 dart2js.js_emitter;
 
 class ParameterStubGenerator {
   static final Set<Selector> emptySelectorSet = new Set<Selector>();
 
   final Namer namer;
@@ skipping 107 matching lines @@
 
     var body;  // List or jsAst.Statement.
     if (member.hasFixedBackendName) {
       body = emitterTask.nativeEmitter.generateParameterStubStatements(
           member, isInterceptedMethod, namer.invocationName(selector),
           parametersBuffer, argumentsBuffer,
           indexOfLastOptionalArgumentInParameters);
     } else if (member.isInstanceMember) {
       if (needsSuperGetter(member)) {
         ClassElement superClass = member.enclosingClass;
-        String methodName = namer.instanceMethodName(member);
+        jsAst.Name methodName = namer.instanceMethodName(member);
         // When redirecting, we must ensure that we don't end up in a subclass.
         // We thus can't just invoke `this.foo$1.call(filledInArguments)`.
         // Instead we need to call the statically resolved target.
         //   `<class>.prototype.bar$1.call(this, argument0, ...)`.
         body = js.statement(
             'return #.#.call(this, #);',
             [backend.emitter.prototypeAccess(superClass,
                                              hasBeenInstantiated: true),
              methodName,
              argumentsBuffer]);
       } else {
         body = js.statement(
             'return this.#(#);',
             [namer.instanceMethodName(member), argumentsBuffer]);
       }
     } else {
       body = js.statement('return #(#)',
           [emitter.staticFunctionAccess(member), argumentsBuffer]);
     }
 
     jsAst.Fun function = js('function(#) { #; }', [parametersBuffer, body]);
 
-    String name = namer.invocationName(selector);
-    String callName =
+    jsAst.Name name = namer.invocationName(selector);
+    jsAst.Name callName =
         (callSelector != null) ? namer.invocationName(callSelector) : null;
     return new ParameterStubMethod(name, callName, function);
   }
 
   // We fill the lists depending on possible/invoked selectors. For example,
   // take method foo:
   //    foo(a, b, {c, d});
   //
   // We may have multiple ways of calling foo:
   // (1) foo(1, 2);
@@ skipping 111 matching lines @@
             generateParameterStub(member, selector, null);
         if (stub != null) {
           stubs.add(stub);
         }
       }
     }
 
     return stubs;
   }
 }