dart2js: Fix hints in code base.

pkg/compiler/lib/src/resolution/constructors.dart

Index: pkg/compiler/lib/src/resolution/constructors.dart
diff --git a/pkg/compiler/lib/src/resolution/constructors.dart b/pkg/compiler/lib/src/resolution/constructors.dart
index 27f7ed294d5236e6f8ba3f36d8138d9932cc9a64..977b688d8f373e252d9f5590cbbc417748ada77f 100644
--- a/pkg/compiler/lib/src/resolution/constructors.dart
+++ b/pkg/compiler/lib/src/resolution/constructors.dart
@@ -42,7 +42,6 @@ class InitializerResolver {
   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) {
@@ -103,7 +102,6 @@ class InitializerResolver {
                                     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);
@@ -253,7 +251,6 @@ class InitializerResolver {
             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) {