Fix crash in RequestSenderTest.RequestSendSuccess.

components/update_client/ping_manager_unittest.cc

Index: components/update_client/ping_manager_unittest.cc
diff --git a/components/update_client/ping_manager_unittest.cc b/components/update_client/ping_manager_unittest.cc
index 1d201887ba83a42543f807de52dd573a26510ba4..9795d6762e050c5e49678888183dbc05794bbcb7 100644
--- a/components/update_client/ping_manager_unittest.cc
+++ b/components/update_client/ping_manager_unittest.cc
@@ -175,6 +175,9 @@ TEST_F(ComponentUpdaterPingManagerTest, PingManagerTest) {
           "download_time_ms=\"9870\"/></app>"))
       << interceptor->GetRequestsAsString();
   interceptor->Reset();
+
+  interceptor_factory.reset();
+  base::RunLoop().RunUntilIdle();
 }
 
 // Tests that sending the ping fails when the component requires encryption but