dart2js: Fix hints in code base.

pkg/compiler/lib/src/js_emitter/old_emitter/class_emitter.dart

 // Copyright (c) 2013, 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 ClassEmitter extends CodeEmitterHelper {
 
   ClassStubGenerator get _stubGenerator =>
       new ClassStubGenerator(compiler, namer, backend);
@@ skipping 372 matching lines @@
           element, 'Expected a ClassElement or a LibraryElement.');
     }
 
     // If the class is never instantiated we still need to set it up for
     // inheritance purposes, but we can simplify its JavaScript constructor.
     bool isInstantiated =
         compiler.codegenWorld.directlyInstantiatedClasses.contains(element);
 
     void visitField(Element holder, FieldElement field) {
       assert(invariant(element, field.isDeclaration));
-      String name = field.name;
 
       // Keep track of whether or not we're dealing with a field mixin
       // into a native class.
       bool isMixinNativeField =
           isClass && element.isNative && holder.isMixinApplication;
 
       // See if we can dynamically create getters and setters.
       // We can only generate getters and setters for [element] since
       // the fields of super classes could be overwritten with getters or
       // setters.
@@ skipping 152 matching lines @@
         ? new Selector.getter(member.name, member.library)
         : new Selector.setter(member.name, member.library);
     String reflectionName = emitter.getReflectionName(selector, name);
     if (reflectionName != null) {
       var reflectable =
           js(backend.isAccessibleByReflection(member) ? '1' : '0');
       builder.addProperty('+$reflectionName', reflectable);
     }
   }
 }