Reenable test.dart to be invoked from dartium checkout

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 648 matching lines @@
         }
         args.addAll(['--libdir=$libdir',
                              '--compile-only',
                              '--out=$outputFile']);
         args.addAll(vmOptions);
         args.add(inputFile);
         break;
       default:
         Expect.fail('unimplemented compiler $compiler');
     }
+    if (executable.endsWith('.dart')) {
+      // Run the compiler script via the Dart VM.
+      args.insertRange(0, 1, executable);
+      executable = TestUtils.dartShellFileName(configuration);
+    }
     return new Command(executable, args);
   }
 
   bool get requiresCleanTemporaryDirectory() =>
       configuration['compiler'] == 'dartc';
 
   /**
    * Create a directory for the generated test.  If a Dart language test
    * needs to be run in a browser, the Dart test needs to be embedded in
    * an HTML page, with a testing framework based on scripting and DOM events.
@@ skipping 571 matching lines @@
         return 'compiler/bin/dartc$suffix';
       case 'frog':
       case 'dart2js':
         return 'frog/bin/frog$suffix';
       default:
         throw "Unknown compiler for: ${configuration['compiler']}";
     }
   }
 
   static String dartShellFileName(Map configuration) {
-    var name = '${buildDir(configuration)}/${executableName(configuration)}';
+    var name = configuration['dart'];
+    if (name == '') {
+      name = '${buildDir(configuration)}/${executableName(configuration)}';
+    }
     if (!(new File(name)).existsSync() && !configuration['list']) {
       throw "Executable '$name' does not exist";
     }
     return name;
   }
 
   static String compilerPath(Map configuration) {
     if (configuration['compiler'] == 'none') {
       return null;  // No separate compiler for dartium tests.
     }
@@ skipping 104 matching lines @@
  * $noCrash tests are expected to be flaky but not crash
  * $pass tests are expected to pass
  * $failOk tests are expected to fail that we won't fix
  * $fail tests are expected to fail that we should fix
  * $crash tests are expected to crash that we should fix
  * $timeout tests are allowed to timeout
 """;
     print(report);
    }
 }