Remove runtime 'dart_app' as it became identical to 'vm'.

tools/testing/dart/test_suite.dart

 // Copyright (c) 2012, 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.
 
 /**
  * Classes and methods for enumerating and preparing tests.
  *
  * This library includes:
  *
  * - Creating tests by listing all the Dart files in certain directories,
@@ skipping 1813 matching lines @@
       "otherScripts": const [],
       "isMultitest": false,
       "isMultiHtmlTest": false,
       "subtestNames": const [],
       "isolateStubs": '',
       "containsDomImport": false,
     };
   }
 
   List<List<String>> getVmOptions(Map optionsFromFile) {
-    var COMPILERS = const ['none', 'precompiler', 'dart2app', 'dart2appjit'];
+    var COMPILERS = const ['none', 'precompiler', 'app_jit'];
     var RUNTIMES = const [
       'none',
       'dart_precompiled',
-      'dart_app',
       'vm',
       'drt',
       'dartium',
       'ContentShellOnAndroid',
       'DartiumOnAndroid'
     ];
     var needsVmOptions = COMPILERS.contains(configuration['compiler']) &&
         RUNTIMES.contains(configuration['runtime']);
     if (!needsVmOptions) return [[]];
     final vmOptions = optionsFromFile['vmOptions'];
@@ skipping 684 matching lines @@
       }
       if (path.length > WINDOWS_SHORTEN_PATH_LIMIT) {
         ++shortNameCounter;
         var pathEnd = path.substring(path.length - WINDOWS_PATH_END_LENGTH);
         path = "short${shortNameCounter}_$pathEnd";
       }
     }
     return path;
   }
 }