Add get_drt.py to test.dart, so that testing browser components updates DumpRenderTree.

tools/testing/dart/drt_updater.dart

Index: tools/testing/dart/drt_updater.dart
diff --git a/tools/testing/dart/drt_updater.dart b/tools/testing/dart/drt_updater.dart
new file mode 100644
index 0000000000000000000000000000000000000000..794df4460ca854bd75fc5d76f8b8e49506cc2c60
--- /dev/null
+++ b/tools/testing/dart/drt_updater.dart
@@ -0,0 +1,49 @@
+// 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.
+
+#library("drt_updater");
+
+#import("dart:io");
+
+class DumpRenderTreeUpdater {
+  static bool isActive = false;
+  static bool updated = false;
+  static List onUpdated;
+
+  static Process updatingProcess;

[Mads Ager (google), 2012/03/12 14:09:20]

Make this private?

[Bill Hesse, 2012/03/12 18:13:35]

Done.

+
+  static void update() {
+    if (!isActive) {
+      isActive = true;
+      print('Updating DumpRenderTree.');
+      onUpdated = [() {updated = true;} ];
+      updatingProcess = new Process.start('python', [getDrtPath]);
+      updatingProcess.onExit = onUpdatedHandler;
+      updatingProcess.onError = (error) {
+        print("Error starting get_drt.py process: $error");
+        onUpdatedHandler(-1);  // Continue anyway.
+      };
+    }
+  }
+
+  static bool componentRequiresDRT(String component) =>
+      const <String>['dartium',

[Mads Ager (google), 2012/03/12 14:09:20]

return TestUtils.isBrowserComponent(component)?

[Bill Hesse, 2012/03/12 18:13:35]

This is an open question - should these be assumed to have the same semantics? 
In which case, which library should import the other?  This will be a circular
dependency, while this way drt_updater has no dependency on anything.  I'll
change this later, if you want.


And now, after the changes, they are different: webdriver is a browser test, but
not a DRT test.

+                     'chromium',
+                     'frogium',
+                     'legium',
+                     'webdriver'].some((x) => x == component);

[vsm, 2012/03/12 15:53:21]

webdriver shouldn't need DRT.  It'll use chrome (or another browser) instead.

[Bill Hesse, 2012/03/12 18:13:35]

Done.

+
+  static String get getDrtPath() {

[Mads Ager (google), 2012/03/12 14:09:20]

Make this private?

[Bill Hesse, 2012/03/12 18:13:35]

Done.

+    String scriptPath = new Options().script.replaceAll('\\', '/');
+    String toolsDir = scriptPath.substring(0, scriptPath.lastIndexOf('/'));
+    return '$toolsDir/get_drt.py';
+  }
+
+  static void onUpdatedHandler(int exit_code) {

[Mads Ager (google), 2012/03/12 14:09:20]

Make this private.

[Bill Hesse, 2012/03/12 18:13:35]

Done.

+    // blah blah blah

[Bill Hesse, 2012/03/12 13:38:32]

Remove Bob Loblaw.

[Bill Hesse, 2012/03/12 18:13:35]

Done.

+    print('DumpRenderTree updated($exit_code)');

[Mads Ager (google), 2012/03/12 14:09:20]

Space between "updated" and "($exit_code)"?

[Bill Hesse, 2012/03/12 18:13:35]

Done.

+    for (var callback in onUpdated ) callback();

[Mads Ager (google), 2012/03/12 14:09:20]

Remove trailing space after onUpdated.

[Bill Hesse, 2012/03/12 18:13:35]

Done.

+  }
+
+}