[infra] Add mirrors WATCHLIST.

WATCHLISTS

 # 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.
 
 # Watchlist Rules
 # Refer: http://dev.chromium.org/developers/contributing-code/watchlists
 
 {
   'WATCHLIST_DEFINITIONS': {
     'build': {
@@ skipping 17 matching lines @@
         'pkg/compiler/lib/src/diagnostics/messages\\.dart|'
         'pkg/analyzer/lib/src/analysis_options/error/option_codes\\.dart|'
         'pkg/analyzer/lib/src/dart/error/hint_codes\\.dart|'
         'pkg/analyzer/lib/src/dart/error/lint_codes\\.dart|'
         'pkg/analyzer/lib/src/dart/error/todo_codes\\.dart|'
         'pkg/analyzer/lib/src/html/error/html_codes\\.dart|'
         'pkg/dart_messages/lib/shared_messages\\.dart'
         ')$'
       )
     },
+    'mirrors' : {
+      'filepath': '.*mirrors.*',
+    },
     'observatory': {
       'filepath': (
         '^runtime/bin/vmservice/|'
         '^runtime/bin/vmservice*|'
         '^runtime/observatory/|'
         '^runtime/vm/service/|'
         '^runtime/vm/service*'
       )
     },
     'runtime': {
       'filepath': '^runtime/',
     },
   },
 
   'WATCHLISTS': {
     'build': [ 'zra@google.com' ],
     'front_end': [ 'dart-fe-team+reviews@google.com' ],
     'messages_review': [ 'dart-uxr+reviews@google.com' ],
+    'mirrors' : [ 'rmacnak@google.com' ],
     'observatory': [ 'turnidge@google.com', 'rmacnak@google.com' ],
     'runtime': [ 'vm-dev@dartlang.org' ],
   },
 }