Use symbol literals in the mirror tests. (Except for void, the empty string and setters.)

tests/lib/mirrors/equality_test.dart

 // Copyright (c) 2013, 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.
 
 // This tests uses the multi-test "ok" feature:
 // none: Trimmed behaviour. Passing on the VM.
 // 01: Trimmed version for dart2js.
 // 02: Full version passing in the VM.
 //
 // TODO(rmacnak,ahe): Remove multi-test when VM and dart2js are on par.
@@ skipping 81 matching lines @@
     {'reflect(3+4)' : reflect(3+4),
      'reflect(6+1)' : reflect(6+1)},
 
     {'reflect("foo")' : reflect("foo"),
      'reflect("foo"), again' : reflect("foo")},
 
     {'currentMirrorSystem().voidType' : currentMirrorSystem().voidType},  /// 01: ok
 
     {'currentMirrorSystem().voidType' : currentMirrorSystem().voidType,   /// 02: ok
      'thisLibrary.functions[#subroutine].returnType' :                    /// 02: ok
-          thisLibrary.functions[const Symbol('subroutine')].returnType},  /// 02: ok
+          thisLibrary.functions[#subroutine].returnType},  /// 02: ok
 
     {'currentMirrorSystem().dynamicType' : currentMirrorSystem().dynamicType,
      'thisLibrary.functions[#main].returnType' :
-          thisLibrary.functions[const Symbol('main')].returnType},
+          thisLibrary.functions[#main].returnType},
 
     {'reflectClass(A)' : reflectClass(A),
-     'thisLibrary.classes[#A]' : thisLibrary.classes[const Symbol('A')],
+     'thisLibrary.classes[#A]' : thisLibrary.classes[#A],
      'reflect(new A<int>()).type.originalDeclaration' :
           reflect(new A<int>()).type.originalDeclaration},
 
     {'reflectClass(B).superclass' : reflectClass(B).superclass,  /// 02: ok
      'reflect(new A<int>()).type' : reflect(new A<int>()).type}, /// 02: ok
 
     {'reflectClass(B)' : reflectClass(B),
-     'thisLibrary.classes[#B]' : thisLibrary.classes[const Symbol('B')],
+     'thisLibrary.classes[#B]' : thisLibrary.classes[#B],
      'reflect(new B()).type' : reflect(new B()).type},
 
     {'thisLibrary' : thisLibrary,
      'reflectClass(A).owner' : reflectClass(A).owner,
      'reflectClass(B).owner' : reflectClass(B).owner,
      'reflect(new A()).type.owner' : reflect(new A()).type.owner,
      'reflect(new B()).type.owner' : reflect(new B()).type.owner},
   ]);
 }