Fix 56 hints in pkg/compiler

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

 // Copyright (c) 2014, 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.
 
 library dart2js.js_emitter.program_builder;
 
 import 'js_emitter.dart' show computeMixinClass;
 import 'model.dart';
 
 import '../common.dart';
@@ skipping 314 matching lines @@
     ClassStubGenerator classStubGenerator =
         new ClassStubGenerator(_compiler, namer, backend);
     RuntimeTypeGenerator runtimeTypeGenerator =
         new RuntimeTypeGenerator(_compiler, _task, namer);
 
     void visitMember(ClassElement enclosing, Element member) {
       assert(invariant(element, member.isDeclaration));
       assert(invariant(element, element == enclosing));
 
       if (Elements.isNonAbstractInstanceMember(member)) {
-        js.Expression code = backend.generatedCode[member];
         // TODO(herhut): Remove once _buildMethod can no longer return null.
         Method method = _buildMethod(member);
         if (method != null) methods.add(method);
       }
       if (member.isGetter || member.isField) {
         Set<Selector> selectors =
             _compiler.codegenWorld.invokedNames[member.name];
         if (selectors != null && !selectors.isEmpty) {
 
           Map<String, js.Expression> callStubsForMember =
@@ skipping 410 matching lines @@
       _registry.registerConstant(outputUnit, constantValue);
       assert(!_constants.containsKey(constantValue));
       String name = namer.constantName(constantValue);
       String constantObject = namer.globalObjectForConstant(constantValue);
       Holder holder = _registry.registerHolder(constantObject);
       Constant constant = new Constant(name, holder, constantValue);
       _constants[constantValue] = constant;
     }
   }
 }