Ib9e095430fa82be2327dcf7fd01ee4275b17415f introduced loops in "_run"
methods which have the side effect of events no longer being set.
Some tests are running until timeout expiration.
Test id Runtime
-------------------------------------------------------------- --------
tests.unit.test_gerrit.TestPolling.test_config_update 123.778
tests.unit.test_gerrit.TestPolling.test_post 123.729
tests.unit.test_gerrit.TestChecksApi.test_new_patchset 123.635
tests.unit.test_gerrit.TestPolling.test_tag 123.628
By changing the subclass method used to set event to one inside the
loop, notifications are restored.
Test id Runtime
-------------------------------------------------------------- --------
tests.unit.test_gerrit.TestPolling.test_config_update 5.246
tests.unit.test_gerrit.TestPolling.test_post 5.252
tests.unit.test_gerrit.TestChecksApi.test_new_patchset 5.276
tests.unit.test_gerrit.TestPolling.test_tag 5.247
Change-Id: I8c9ad6577d43b9b4866f83e4f8727615abf239c4