Media Galleries API: Fix MediaGalleriesPreferences finders race.

chrome/browser/media_galleries/media_galleries_permissions_unittest.cc

Index: chrome/browser/media_galleries/media_galleries_permissions_unittest.cc
diff --git a/chrome/browser/media_galleries/media_galleries_permissions_unittest.cc b/chrome/browser/media_galleries/media_galleries_permissions_unittest.cc
index c2af8aa82a7db1f6f6b26acc1d31f73dcb88cab4..d233796cbe365e1c3df2e10ef67c4248fd9ada8d 100644
--- a/chrome/browser/media_galleries/media_galleries_permissions_unittest.cc
+++ b/chrome/browser/media_galleries/media_galleries_permissions_unittest.cc
@@ -3,13 +3,17 @@
 // found in the LICENSE file.
 
 #include "base/memory/scoped_ptr.h"
+#include "base/run_loop.h"
 #include "chrome/browser/extensions/extension_prefs.h"
 #include "chrome/browser/extensions/extension_prefs_unittest.h"
 #include "chrome/browser/extensions/extension_service.h"
 #include "chrome/browser/extensions/extension_system.h"
 #include "chrome/browser/media_galleries/media_galleries_preferences.h"
+#include "chrome/browser/media_galleries/media_galleries_test_util.h"
 #include "chrome/browser/storage_monitor/test_storage_monitor.h"
 #include "chrome/test/base/testing_profile.h"
+#include "content/public/browser/browser_thread.h"
+#include "content/public/test/test_browser_thread_bundle.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
 namespace {
@@ -55,6 +59,10 @@ class MediaGalleriesPermissionsTest : public extensions::ExtensionPrefsTest {
     ASSERT_TRUE(TestStorageMonitor::CreateAndInstall());
     profile_.reset(new TestingProfile);
     gallery_prefs_.reset(new MediaGalleriesPreferences(profile_.get()));
+    base::RunLoop loop;
+    gallery_prefs_->EnsureInitialized(loop.QuitClosure());
+    loop.Run();
+
     gallery_prefs_->SetExtensionPrefsForTesting(prefs());
 
     extension1_id_ = prefs_.AddExtensionAndReturnId("test1");
@@ -134,6 +142,10 @@ class MediaGalleriesPermissionsTest : public extensions::ExtensionPrefsTest {
   std::vector<MediaGalleryPermission> extension3_expectation_;
   std::vector<MediaGalleryPermission> extension4_expectation_;
 
+  // Needed for |gallery_prefs_| to initialize correctly.
+  EnsureMediaDirectoriesExists ensure_media_directories_exists_;
+  content::TestBrowserThreadBundle thread_bundle_;
+
   scoped_ptr<TestingProfile> profile_;
   scoped_ptr<MediaGalleriesPreferences> gallery_prefs_;
 };