Remove MIPS support

tools/testing/dart/compiler_configuration.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.
 
 import 'dart:io';
 
 import 'command.dart';
 import 'configuration.dart';
 import 'path.dart';
 import 'runtime_configuration.dart';
@@ skipping 704 matching lines @@
     }
 
     String ccFlags;
     switch (arch) {
       case Architecture.x64:
       case Architecture.simarm64:
         ccFlags = "-m64";
         break;
       case Architecture.ia32:
       case Architecture.simarm:
-      case Architecture.simmips:
-        ccFlags = "-m32";
-        break;
       case Architecture.arm:
       case Architecture.arm64:
         ccFlags = null;
         break;
-      case Architecture.mips:
-        ccFlags = "-EL";
-        break;
       default:
         throw "Architecture not supported: ${arch.name}";
     }
 
     var exec = cc;
     var args = <String>[];
     if (ccFlags != null) args.add(ccFlags);
     if (ldFlags != null) args.add(ldFlags);
     args.add(shared);
     args.add('-nostdlib');
@@ skipping 192 matching lines @@
       RuntimeConfiguration runtimeConfiguration,
       String buildDir,
       TestInformation info,
       List<String> vmOptions,
       List<String> sharedOptions,
       List<String> originalArguments,
       CommandArtifact artifact) {
     return <String>[];
   }
 }