dart2js: Fix hints in code base.

pkg/compiler/lib/src/resolution/constructors.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 resolution;
 
 class InitializerResolver {
   final ResolverVisitor visitor;
   final Map<Element, Node> initialized;
   Link<Node> initializers;
@@ skipping 24 matching lines @@
         init,
         MessageKind.DUPLICATE_INITIALIZER, {'fieldName': field.name});
     visitor.compiler.reportInfo(
         existing,
         MessageKind.ALREADY_INITIALIZED, {'fieldName': field.name});
   }
 
   void checkForDuplicateInitializers(FieldElementX field, Node init) {
     // [field] can be null if it could not be resolved.
     if (field == null) return;
-    String name = field.name;
     if (initialized.containsKey(field)) {
       reportDuplicateInitializerError(field, init, initialized[field]);
     } else if (field.isFinal) {
       field.parseNode(visitor.compiler);
       Expression initializer = field.initializer;
       if (initializer != null) {
         reportDuplicateInitializerError(field, init, initializer);
       }
     }
     initialized[field] = init;
@@ skipping 40 matching lines @@
         return lookupTarget.supertype.element;
       }
     }
     return lookupTarget;
   }
 
   Element resolveSuperOrThisForSend(FunctionElement constructor,
                                     FunctionExpression functionNode,
                                     Send call) {
     // Resolve the selector and the arguments.
-    ResolverTask resolver = visitor.compiler.resolver;
     visitor.inStaticContext(() {
       visitor.resolveSelector(call, null);
       visitor.resolveArguments(call.argumentsNode);
     });
     Selector selector = registry.getSelector(call);
     bool isSuperCall = Initializers.isSuperConstructorCall(call);
 
     ClassElement lookupTarget = getSuperOrThisLookupTarget(constructor,
                                                            isSuperCall,
                                                            call);
@@ skipping 129 matching lines @@
           if (functionNode.hasBody() && !constructor.isConst) {
             error(functionNode, MessageKind.REDIRECTING_CONSTRUCTOR_HAS_BODY);
           }
           // Check that there are no other initializers.
           if (!initializers.tail.isEmpty) {
             error(call, MessageKind.REDIRECTING_CONSTRUCTOR_HAS_INITIALIZER);
           } else {
             constructor.isRedirectingGenerative = true;
           }
           // Check that there are no field initializing parameters.
-          Compiler compiler = visitor.compiler;
           FunctionSignature signature = constructor.functionSignature;
           signature.forEachParameter((ParameterElement parameter) {
             if (parameter.isInitializingFormal) {
               Node node = parameter.node;
               error(node, MessageKind.INITIALIZING_FORMAL_NOT_ALLOWED);
             }
           });
           return resolveSuperOrThisForSend(constructor, functionNode, call);
         } else {
           visitor.error(call, MessageKind.CONSTRUCTOR_CALL_EXPECTED);
@@ skipping 204 matching lines @@
     return element;
   }
 
   /// Assumed to be called by [resolveRedirectingFactory].
   Element visitRedirectingFactoryBody(RedirectingFactoryBody node) {
     Node constructorReference = node.constructorReference;
     return finishConstructorReference(visit(constructorReference),
         constructorReference, node);
   }
 }