Use callbacks in SessionRestore unit tests

chrome/browser/sessions/session_restore_test_helper.cc

Index: chrome/browser/sessions/session_restore_test_helper.cc
diff --git a/chrome/browser/sessions/session_restore_test_helper.cc b/chrome/browser/sessions/session_restore_test_helper.cc
new file mode 100644
index 0000000000000000000000000000000000000000..c64395a790e2ec76c9de156c30e6dabb5cffff9e
--- /dev/null
+++ b/chrome/browser/sessions/session_restore_test_helper.cc
@@ -0,0 +1,35 @@
+// Copyright (c) 2014 The Chromium Authors. All rights reserved.

[sky, 2015/01/26 16:50:01]

2015 and no copyright.

[Simon Que, 2015/01/26 18:40:49]

Done.

+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/sessions/session_restore_test_helper.h"
+
+#include "content/public/test/test_utils.h"
+#include "testing/gtest/include/gtest/gtest.h"
+
+SessionRestoreTestHelper::SessionRestoreTestHelper()
+    : restore_notification_seen_(false),
+      loop_is_running_(false) {
+  callback_subscription_ = SessionRestore::RegisterOnSessionRestoredCallback(
+      base::Bind(&SessionRestoreTestHelper::OnSessionRestoreDone,
+                 base::Unretained(this)));

[sky, 2015/01/26 16:50:01]

As it's entirely possible for this to be destroyed before you get the callback
you shouldn't use unretained here.

[Simon Que, 2015/01/26 18:40:49]

Done.

+}
+
+void SessionRestoreTestHelper::Wait() {
+  if (restore_notification_seen_)
+    return;
+
+  loop_is_running_ = true;
+  message_loop_runner_ = new content::MessageLoopRunner;
+  message_loop_runner_->Run();
+  EXPECT_TRUE(restore_notification_seen_);
+}
+
+void SessionRestoreTestHelper::OnSessionRestoreDone() {
+  restore_notification_seen_ = true;
+  if (!loop_is_running_)
+    return;
+
+  message_loop_runner_->Quit();
+  loop_is_running_ = false;
+}