bug 1592532 - reinstate filtering client certificates by usage (reverts behavior from bug 1267643) r=kjacobs

Differential Revision: https://phabricator.services.mozilla.com/D52062

--HG--
extra : moz-landing-system : lando

security/manager/ssl/nsNSSIOLayer.cpp

@@ -1842,6 +1842,10 @@ void ClientAuthDataRunnable::RunOnTargetThread() {
   if (mRV != SECSuccess) {
     return;
   }
+  mRV = CERT_FilterCertListByUsage(certList.get(), certUsageSSLClient, false);
+  if (mRV != SECSuccess) {
+    return;
+  }
   if (CERT_LIST_EMPTY(certList)) {
     return;
   }