[Sync] Fix namespaces for the browser_sync component.

components/browser_sync/signin_confirmation_helper.cc

Index: components/browser_sync/signin_confirmation_helper.cc
diff --git a/components/browser_sync/signin_confirmation_helper.cc b/components/browser_sync/signin_confirmation_helper.cc
index b5a5c5fa504144689c72f5d659658e360791f0e9..0a59831753c3f2e488b16bb124a10b60012f1dfe 100644
--- a/components/browser_sync/signin_confirmation_helper.cc
+++ b/components/browser_sync/signin_confirmation_helper.cc
@@ -13,6 +13,8 @@
 #include "components/history/core/browser/history_service.h"
 #include "components/history/core/browser/history_types.h"
 
+namespace browser_sync {
+
 namespace {
 
 // Determines whether there are any typed URLs in a history backend.
@@ -44,8 +46,6 @@ class HasTypedURLsTask : public history::HistoryDBTask {
 
 }  // namespace
 
-namespace sync_driver {
-
 SigninConfirmationHelper::SigninConfirmationHelper(
     history::HistoryService* history_service,
     const base::Callback<void(bool)>& return_result)
@@ -117,4 +117,4 @@ void SigninConfirmationHelper::ReturnResult(bool result) {
   }
 }
 
-}  // namespace sync_driver
+}  // namespace browser_sync