Fix some users of removed mirror API.

pkg/docgen/test/single_library_test.dart

 library single_library_test;
 
 import 'dart:io';
 
 import 'package:path/path.dart' as path;
 import 'package:unittest/unittest.dart';
 
 import '../lib/docgen.dart';
 
 const String DART_LIBRARY = '''
@@ skipping 97 matching lines @@
 
           /// Testing fixReference
           // Testing Doc comment for class [A].
           var libraryMirror = mirrorSystem.libraries[testLibraryUri];
           var classMirror = libraryMirror.classes.values.first;
           var classDocComment = fixReference('A', libraryMirror,
               classMirror, null).children.first.text;
           expect(classDocComment == 'test.A', isTrue);
 
           // Test for linking to parameter [A]
-          var methodMirror = classMirror.methods['doThis'];
+          var methodMirror = classMirror.declarations['doThis'];

[gbracha, 2013/11/07 00:09:11]

#doThis?

[rmacnak, 2013/11/07 00:18:29]

Actually, undoing this change. These aren't dart:mirrors.

           var methodParameterDocComment = fixReference('A', libraryMirror,
               classMirror, methodMirror).children.first.text;
           // TODO(alanknight) : We're not supporting linking to parameters yet
           // expect(methodParameterDocComment == 'test.A.doThis#A', isTrue);
 
           // Testing trying to refer to doThis function
           var methodDocComment = fixReference('doThis', libraryMirror,
               classMirror, methodMirror).children.first.text;
           expect(methodDocComment == 'test.A.doThis', isTrue);
 
           // Testing something with no reference
           var libraryDocComment = fixReference('foobar', libraryMirror,
               classMirror, methodMirror).children.first.text;
           expect(libraryDocComment == 'foobar', isTrue);
         })).whenComplete(() => temporaryDir.deleteSync(recursive: true));
     });
   });
 }