dart2js: Fix hints in code base.

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 65 matching lines @@
     if (isInterceptedMethod) {
       count++;
       parametersBuffer[0] = new jsAst.Parameter(receiverArgumentName);
       argumentsBuffer[0] = js('#', receiverArgumentName);
     }
 
     int optionalParameterStart = positionalArgumentCount + extraArgumentCount;
     // Includes extra receiver argument when using interceptor convention
     int indexOfLastOptionalArgumentInParameters = optionalParameterStart - 1;
 
-    int parameterIndex = 0;
     parameters.orderedForEachParameter((ParameterElement element) {
       String jsName = backend.namer.safeVariableName(element.name);
       assert(jsName != receiverArgumentName);
       if (count < optionalParameterStart) {
         parametersBuffer[count] = new jsAst.Parameter(jsName);
         argumentsBuffer[count] = js('#', jsName);
       } else {
         int index = names.indexOf(element.name);
         if (index != -1) {
           indexOfLastOptionalArgumentInParameters = count;
@@ skipping 175 matching lines @@
             generateParameterStub(member, selector, null);
         if (stub != null) {
           stubs.add(stub);
         }
       }
     }
 
     return stubs;
   }
 }