Remove MIPS support

tools/gardening/lib/src/buildbot_data.dart

 // Copyright (c) 2017, 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.
 
 import 'dart:async';
 import 'buildbot_structures.dart';
 import 'logdog.dart' as logdog;
 import 'util.dart';
 
 /// Data describing the steps of the buildbots.
@@ skipping 79 matching lines @@
         'vm tests',
         'checked vm tests',
       ]),
       const BuildSubgroup(shardNames: const <String>[
         'vm-win-release-ia32-be',
       ], testSteps: const <String>[
         'vm tests',
         'checked vm tests',
       ]),
       const BuildSubgroup(shardNames: const <String>[
-        'vm-linux-debug-simmips-be',
-      ], testSteps: const <String>[
-        'vm tests',
-        'checked vm tests',
-      ]),
-      const BuildSubgroup(shardNames: const <String>[
-        'vm-linux-release-simmips-be',
-      ], testSteps: const <String>[
-        'vm tests',
-        'checked vm tests',
-      ]),
-      const BuildSubgroup(shardNames: const <String>[
         'vm-linux-debug-simarm-be',
       ], testSteps: const <String>[
         'vm tests',
         'checked vm tests',
       ]),
       const BuildSubgroup(shardNames: const <String>[
         'vm-linux-release-simarm-be',
       ], testSteps: const <String>[
         'vm tests',
         'checked vm tests',
@@ skipping 825 matching lines @@
           stepNames.add(step);
         }
       }
       if (stepNames.isNotEmpty) {
         subgroups[subgroup] = stepNames;
       }
     }
   }
   return subgroups;
 }