Do the ReloadLocaleResources() call on the IO thread to avoid synchronization issues.

chrome/test/base/ui_test_utils.h

Index: chrome/test/base/ui_test_utils.h
diff --git a/chrome/test/base/ui_test_utils.h b/chrome/test/base/ui_test_utils.h
index 086d084c2ec9c2eff9da38e89a056d13441d80d9..2638722ec3c112757c402d0356eb782b4888a886 100644
--- a/chrome/test/base/ui_test_utils.h
+++ b/chrome/test/base/ui_test_utils.h
@@ -55,6 +55,10 @@ class TabContents;
 typedef TabContents TabContentsWrapper;
 class TemplateURLService;
 
+namespace base {
+class WaitableEvent;
+}
+
 namespace browser {
 struct NavigateParams;
 }
@@ -127,6 +131,10 @@ void WaitForLoadStop(content::WebContents* tab);
 // Use BrowserAddedObserver instead.
 Browser* WaitForNewBrowser();
 
+// Waits for |event| to be signaled running message loop in the current thread
+// while waiting.
+void WaitEventSignaled(base::WaitableEvent* event);
+
 // Opens |url| in an incognito browser window with the incognito profile of
 // |profile|, blocking until the navigation finishes. This will create a new
 // browser if a browser with the incognito profile does not exist.