Fix flush race triggered from TracingServiceImpl::StartTracing am: c388978ab5
Fix flush race triggered from TracingServiceImpl::StartTracing am: c388978ab5

Original change: https://android-review.googlesource.com/c/platform/external/perfetto/+/1966499

Change-Id: I8ecd8bdd6287ce08544be619f0650523ffd1f557

google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto,google/perfetto