Remove more type casts

pkg/analyzer/lib/src/generated/error.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 analyzer.src.generated.error;
 
 import 'dart:collection';
 
 import 'package:analyzer/dart/ast/ast.dart' show AstNode;
 import 'package:analyzer/dart/ast/token.dart';
@@ skipping 125 matching lines @@
     return hashCode;
   }
 
   /**
    * Return the message to be displayed for this error. The message should
    * indicate what is wrong and why it is wrong.
    */
   String get message => _message;
 
   @override
-  bool operator ==(Object obj) {
-    if (identical(obj, this)) {
+  bool operator ==(Object other) {
+    if (identical(other, this)) {
       return true;
     }
     // prepare other AnalysisError
-    if (obj is! AnalysisError) {
-      return false;
+    if (other is AnalysisError) {
+      // Quick checks.
+      if (!identical(errorCode, other.errorCode)) {
+        return false;
+      }
+      if (offset != other.offset || length != other.length) {
+        return false;
+      }
+      if (isStaticOnly != other.isStaticOnly) {
+        return false;
+      }
+      // Deep checks.
+      if (_message != other._message) {
+        return false;
+      }
+      if (source != other.source) {
+        return false;
+      }
+      // OK
+      return true;
     }
-    AnalysisError other = obj as AnalysisError;
-    // Quick checks.
-    if (!identical(errorCode, other.errorCode)) {
-      return false;
-    }
-    if (offset != other.offset || length != other.length) {
-      return false;
-    }
-    if (isStaticOnly != other.isStaticOnly) {
-      return false;
-    }
-    // Deep checks.
-    if (_message != other._message) {
-      return false;
-    }
-    if (source != other.source) {
-      return false;
-    }
-    // OK
-    return true;
+    return false;
   }
 
   /**
    * Return the value of the given [property], or `null` if the given property
    * is not defined for this error.
    */
   Object/*=V*/ getProperty/*<V>*/(ErrorProperty/*<V>*/ property) => null;
 
   @override
   String toString() {
@@ skipping 5626 matching lines @@
    * Initialize a newly created error code to have the given [name].
    */
   const TodoCode(String name) : super(name, "{0}");
 
   @override
   ErrorSeverity get errorSeverity => ErrorSeverity.INFO;
 
   @override
   ErrorType get type => ErrorType.TODO;
 }