Remove call to GetBlockingPool in RLZ

ios/chrome/browser/rlz/rlz_tracker_delegate_impl.cc

Index: ios/chrome/browser/rlz/rlz_tracker_delegate_impl.cc
diff --git a/ios/chrome/browser/rlz/rlz_tracker_delegate_impl.cc b/ios/chrome/browser/rlz/rlz_tracker_delegate_impl.cc
index ce6606cd5f14152352f38f886fbdf0be42ce7eb7..a8a80acd8bc3d6de1077ffc323d6c1f2296a9740 100644
--- a/ios/chrome/browser/rlz/rlz_tracker_delegate_impl.cc
+++ b/ios/chrome/browser/rlz/rlz_tracker_delegate_impl.cc
@@ -58,10 +58,6 @@ bool RLZTrackerDelegateImpl::IsOnUIThread() {
   return web::WebThread::CurrentlyOn(web::WebThread::UI);
 }
 
-base::SequencedWorkerPool* RLZTrackerDelegateImpl::GetBlockingPool() {
-  return web::WebThread::GetBlockingPool();
-}
-
 net::URLRequestContextGetter* RLZTrackerDelegateImpl::GetRequestContext() {
   return GetApplicationContext()->GetSystemURLRequestContext();
 }