Add a test helper class for ExtensionRegistry.

extensions/browser/extension_test_registry_observer.h

+// Copyright 2014 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.
+
+#ifndef EXTENSIONS_BROWSER_EXTENSION_TEST_REGISTRY_OBSERVER_H_
+#define EXTENSIONS_BROWSER_EXTENSION_TEST_REGISTRY_OBSERVER_H_

[not at google - send to devlin, 2014/06/15 21:20:16]

+yoz, rockot

Can this file go in extensions/test? It would be nice to prepare for a time when
this class can integrate with gtest, and return testing::AssertionResults for
example.

However, it depends on extensions/browser. not sure if that matters.

+
+#include "base/scoped_observer.h"
+#include "content/public/test/test_utils.h"
+#include "extensions/browser/extension_registry.h"

[not at google - send to devlin, 2014/06/15 21:20:16]

forward declare?

[limasdf, 2014/06/16 18:58:53]

Done.

+#include "extensions/browser/extension_registry_observer.h"
+
+namespace extensions {
+
+// A helper class that listen for ExtensionRegistry notifications.
+class ExtensionTestRegistryObserver : public ExtensionRegistryObserver {
+ public:
+  explicit ExtensionTestRegistryObserver(ExtensionRegistry* registry);
+  virtual ~ExtensionTestRegistryObserver();
+
+  void WaitForExtensionInstalled();

[not at google - send to devlin, 2014/06/15 21:20:17]

This should probably be "WaitForExtensionWillBeInstalled" I suppose.

[limasdf, 2014/06/16 18:58:53]

WaitForAnyExtensionWillBeInstalled.

+  void WaitForExtensionUninstalled();

[not at google - send to devlin, 2014/06/15 21:20:17]

I expect that eventually we'll want to be checking for specific extensions being
installed, uninstalled, loaded, unloaded, etc.

In the meantime can you name these WaitForAnyExtensionUninstalled and
WaitForAnyExtensionWillBeInstalled?

Maybe one day we'll have a version of WaitForExtensionUninstalled(const
std::string& id, UninstallReason reason) etc.

+
+ private:
+  virtual void OnExtensionWillBeInstalled(
+      content::BrowserContext* browser_context,
+      const Extension* extension,
+      bool is_update,
+      bool from_ephemeral,
+      const std::string& old_name) OVERRIDE;
+  virtual void OnExtensionUninstalled(content::BrowserContext* browser_context,
+                                      const Extension* extension) OVERRIDE;
+
+  bool waiting_for_installed_;
+  bool received_installed_;
+  scoped_refptr<content::MessageLoopRunner> runner_installed_;
+
+  bool waiting_for_uninstalled_;
+  bool received_uninstalled_;
+  scoped_refptr<content::MessageLoopRunner> runner_uninstalled_;
+
+  ScopedObserver<ExtensionRegistry, ExtensionRegistryObserver>
+      extension_registry_observer_;
+};
+
+}  // namespace extensions
+
+#endif  // EXTENSIONS_BROWSER_EXTENSION_TEST_REGISTRY_OBSERVER_H_