Add a non-blocking "OneShotEvent" class

chrome/browser/extensions/test_extension_system.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/extensions/test_extension_system.h"
 
 #include "base/command_line.h"
 #include "base/prefs/pref_service.h"
 #include "chrome/browser/extensions/api/location/location_manager.h"
 #include "chrome/browser/extensions/blacklist.h"
@@ skipping 162 matching lines @@
 }
 
 ExtensionWarningService* TestExtensionSystem::warning_service() {
   return NULL;
 }
 
 Blacklist* TestExtensionSystem::blacklist() {
   return blacklist_.get();
 }
 
+const OneShotEvent& TestExtensionSystem::ready() const {
+  return ready_;
+}
+
+void TestExtensionSystem::ExtensionServiceReady() { ready_.Signal(); }
+void TestExtensionSystem::MakeReady() { ready_.Signal(); }

[Matt Perry, 2013/05/16 00:55:50]

Might this cause problems since Signal can only be called once?

[Jeffrey Yasskin, 2013/05/16 00:59:20]

Tests could cause a DCHECK by calling MakeReady() twice, but as long as some
trybots run tests in debug mode, we'll catch that. On the other hand, no tests
are actually using this yet; maybe we don't need it.

+
 // static
 ProfileKeyedService* TestExtensionSystem::Build(
     content::BrowserContext* profile) {
   return new TestExtensionSystem(static_cast<Profile*>(profile));
 }
 
 }  // namespace extensions