Fix hints in the analyzer package.

pkg/analyzer/lib/src/generated/incremental_resolver.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 engine.incremental_resolver;
 
 import 'dart:collection';
 import 'dart:math' as math;
 
 import 'package:analyzer/src/services/lint.dart';
@@ skipping 85 matching lines @@
   /**
    * Determines how elements model corresponding to the given [node] differs
    * from the [element].
    */
   DeclarationMatchKind matches(AstNode node, Element element) {
     logger.enter('match $element @ ${element.nameOffset}');
     try {
       _captureEnclosingElements(element);
       _gatherElements(element);
       node.accept(this);
-    } on _DeclarationMismatchException catch (exception) {
+    } on _DeclarationMismatchException {
       return DeclarationMatchKind.MISMATCH;
     } finally {
       logger.exit();
     }
     // no API changes
     if (_removedElements.isEmpty && _addedElements.isEmpty) {
       return DeclarationMatchKind.MATCH;
     }
     // simple API change
     logger.log('_removedElements: $_removedElements');
@@ skipping 223 matching lines @@
       _assertNotNull(element);
       _assertSameAnnotations(node, element);
       _assertEquals(node.isStatic, element.isStatic);
       _assertSameType(node.returnType, element.returnType);
       _assertCompatibleParameters(node.parameters, element.parameters);
       _assertBodyModifiers(node.body, element);
       _removedElements.remove(element);
       // matches, update the existing element
       node.name.staticElement = element;
       _setLocalElements(element, newElement);
-    } on _DeclarationMismatchException catch (e) {
+    } on _DeclarationMismatchException {
       _addedElements.add(newElement);
       _removeElement(element);
       // add new element
       if (newElement is MethodElement) {
         List<MethodElement> methods = _enclosingClass.methods;
         methods.add(newElement);
         _enclosingClass.methods = methods;
       } else {
         List<PropertyAccessorElement> accessors = _enclosingClass.accessors;
         accessors.add(newElement);
@@ skipping 1449 matching lines @@
   @override
   String toString() => name;
 }
 
 class _TokenPair {
   final _TokenDifferenceKind kind;
   final Token oldToken;
   final Token newToken;
   _TokenPair(this.kind, this.oldToken, this.newToken);
 }