Media Galleries API: Fix MediaGalleriesPreferences finders race.

chrome/browser/media_galleries/media_galleries_preferences_unittest.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.
 
 // MediaGalleriesPreferences unit tests.
 
 #include "chrome/browser/media_galleries/media_galleries_preferences.h"
 
 #include "base/command_line.h"
 #include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
+#include "base/run_loop.h"
 #include "base/strings/utf_string_conversions.h"
 #include "base/values.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/extensions/test_extension_system.h"
 #include "chrome/browser/media_galleries/media_file_system_registry.h"
 #include "chrome/browser/media_galleries/media_galleries_test_util.h"
 #include "chrome/browser/storage_monitor/media_storage_util.h"
 #include "chrome/browser/storage_monitor/storage_monitor.h"
 #include "chrome/browser/storage_monitor/test_storage_monitor.h"
 #include "chrome/common/extensions/background_info.h"
@@ skipping 81 matching lines @@
   virtual void SetUp() OVERRIDE {
     ASSERT_TRUE(TestStorageMonitor::CreateAndInstall());
 
     extensions::TestExtensionSystem* extension_system(
         static_cast<extensions::TestExtensionSystem*>(
             extensions::ExtensionSystem::Get(profile_.get())));
     extension_system->CreateExtensionService(
         CommandLine::ForCurrentProcess(), base::FilePath(), false);
 
     gallery_prefs_.reset(new MediaGalleriesPreferences(profile_.get()));
+    base::RunLoop loop;
+    gallery_prefs_->EnsureInitialized(loop.QuitClosure());
+    loop.Run();
 
     // Load the default galleries into the expectations.
     const MediaGalleriesPrefInfoMap& known_galleries =
         gallery_prefs_->known_galleries();
     if (known_galleries.size()) {
       ASSERT_EQ(3U, known_galleries.size());
       default_galleries_count_ = 3;
       MediaGalleriesPrefInfoMap::const_iterator it;
       for (it = known_galleries.begin(); it != known_galleries.end(); ++it) {
         expected_galleries_[it->first] = it->second;
@@ skipping 740 matching lines @@
   info.volume_label = string16();
   EXPECT_EQ(ASCIIToUTF16("vendor, model"), info.GetGalleryDisplayName());
 
   info.device_id = StorageInfo::MakeDeviceId(
       StorageInfo::FIXED_MASS_STORAGE, "unique");
   EXPECT_EQ(base::FilePath(FILE_PATH_LITERAL("unique")).AsUTF8Unsafe(),
             UTF16ToUTF8(info.GetGalleryTooltip()));
 
   TestStorageMonitor::RemoveSingleton();
 }