This patch adds some changes needed to run mochitest android tests in CI for mozperftest. The main change is that we use `runtestsremote.run_test_harness` instead of `runtests.run_test_harness` for running android tests. Additionally, the `LogProcessor` is modified to use the `re.search` method for finding the `perfMetrics` output and remove the requirement for there to be a space after `perfMetrics`. This is done because the output received from mochitest android is always prefixed with something which broke `re.match`. The removal of the space requirement was done to remove a common pitfall that was seen with others writing mozperftest mochitest tests. Differential Revision: https://phabricator.services.mozilla.com/D245766
=========== mozperftest =========== **mozperftest** can be used to run performance tests against browsers. See the docs directory.