[USS] Show USS counters in about:sync page

components/sync/driver/sync_frontend.h

Index: components/sync/driver/sync_frontend.h
diff --git a/components/sync/driver/sync_frontend.h b/components/sync/driver/sync_frontend.h
index 594f85740326fac8f423365f0daf2f7f64d7bb2a..c1415e931335afc05b04bf104cdcd42393e91f6b 100644
--- a/components/sync/driver/sync_frontend.h
+++ b/components/sync/driver/sync_frontend.h
@@ -76,11 +76,11 @@ class SyncFrontend {
       ModelType type,
       const UpdateCounters& counters) = 0;
 
-  // Called when we receive an updated status counter for a directory type.
+  // Called when we receive an updated status counter for a datatype.
   //
   // Disabled by default.  Enable by calling
   // EnableDirectoryTypeDebugInfoForwarding() on the backend.
-  virtual void OnDirectoryTypeStatusCounterUpdated(
+  virtual void OnDatatypeStatusCounterUpdated(
       ModelType type,
       const StatusCounters& counters) = 0;