Disable background thread refreshing GCPW login UI

Bug: 1130024
Change-Id: If0084a50d40a2cec5ab3b1248ab39af66b4f93a9
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2419145
Auto-Submit: Yusuf Sengul <yusufsn@google.com>
Commit-Queue: Rakesh Soma <rakeshsoma@google.com>
Reviewed-by: Rakesh Soma <rakeshsoma@google.com>
Cr-Commit-Position: refs/heads/master@{#808724}

chrome/credential_provider/gaiacp/gaia_credential_provider.cc

@@ -209,7 +209,7 @@ unsigned __stdcall BackgroundTokenHandleUpdater::PeriodicTokenHandleUpdate(
                         "credentials";
     }
 
-    if (GetGlobalFlagOrDefault(kRegUpdateCredentialsOnChange, 1))
+    if (GetGlobalFlagOrDefault(kRegUpdateCredentialsOnChange, 0))
       event_handler->UpdateCredentialsIfNeeded(user_access_changed);
   }