re-add hack to make tests pass, with a TODO

test/cpp/end2end/xds/xds_cluster_end2end_test.cc

@@ -363,6 +363,13 @@ TEST_P(CdsTest, MetricLabels) {
               OptionalLabelComponent::kXdsLocalityLabels,
               ::testing::Pointee(::testing::ElementsAre(::testing::Pair(
                   "grpc.lb.locality", LocalityNameString("locality1")))))));
+  // TODO(yashkt, yijiem): This shutdown shouldn't actually be necessary.
+  // The only reason it's here is to add a delay before
+  // fake_client_call_tracer_factory goes out of scope, since there may
+  // be lingering callbacks in the call stack that are using the
+  // CallAttemptTracer even after we get here, which would then cause a
+  // crash.  Find a cleaner way to fix this.
+  balancer_->Shutdown();
 }
 
 //