Reorganize tests for samples so the test is discoverable from the sample

tools/test.dart

 #!/usr/bin/env dart
 // 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.
 
 /**
  * This file is the entrypoint of the dart test suite.  This suite is used
  * to test:
  *
  *     1. the dart vm
@@ skipping 32 matching lines @@
 /**
  * The directories that contain test suites which follow the conventions
  * required by [StandardTestSuite]'s forDirectory constructor.
  * New test suites should follow this convention because it makes it much
  * simpler to add them to test.dart.  Existing test suites should be
  * moved to here, if possible.
 */
 final TEST_SUITE_DIRECTORIES = [
     new Path('pkg'),
     new Path('runtime/tests/vm'),
-    new Path('samples/tests/samples'),
+    new Path('samples'),
     new Path('tests/benchmark_smoke'),
     new Path('tests/chrome'),
     new Path('tests/compiler/dart2js'),
     new Path('tests/compiler/dart2js_extra'),
     new Path('tests/compiler/dart2js_foreign'),
     new Path('tests/compiler/dart2js_native'),
     new Path('tests/corelib'),
     new Path('tests/html'),
     new Path('tests/isolate'),
     new Path('tests/json'),
@@ skipping 235 matching lines @@
 void main() {
   deleteTemporaryDartDirectories().then((_) {
     var optionsParser = new TestOptionsParser();
     var configurations = optionsParser.parse(new Options().arguments);
     if (configurations != null && configurations.length > 0) {
       testConfigurations(configurations);
     }
   });
 }