[Sync] Fix namespaces for the browser_sync component.

chrome/browser/ui/webui/browsing_history_handler_unittest.cc

Index: chrome/browser/ui/webui/browsing_history_handler_unittest.cc
diff --git a/chrome/browser/ui/webui/browsing_history_handler_unittest.cc b/chrome/browser/ui/webui/browsing_history_handler_unittest.cc
index 1db8488e95bef54fc6dea4520fc97def522a2ca3..97b9bfcbd424413d4a1f4aa666d6e0020de1a35f 100644
--- a/chrome/browser/ui/webui/browsing_history_handler_unittest.cc
+++ b/chrome/browser/ui/webui/browsing_history_handler_unittest.cc
@@ -77,10 +77,11 @@ bool ResultEquals(
 
 void IgnoreBoolAndDoNothing(bool ignored_argument) {}
 
-class TestSyncService : public TestProfileSyncService {
+class TestSyncService : public browser_sync::TestProfileSyncService {
  public:
   explicit TestSyncService(Profile* profile)
-      : TestProfileSyncService(CreateProfileSyncServiceParamsForTest(profile)),
+      : browser_sync::TestProfileSyncService(
+            CreateProfileSyncServiceParamsForTest(profile)),
         sync_active_(true) {}
 
   bool IsSyncActive() const override { return sync_active_; }