ProcStatReader.Threads is flaky because it relies on an internal,
imprecise measurement of boot time. The flaky test asserts that a
thread started after the main thread should have a start time >= the
main thread. The start time is returned in a timeval, with microsecond
precision, but the measurement of boot time requires two system calls
and the time between those system calls can be approximately a
microsecond. An unlucky event such as a change in system time could
make this imprecision arbitrarily bad.
This patch lets the caller of ProcStatReader.StartTime() inject the
boot time, allowing ProcStatReader to guarantee that threads have
correctly ordered time, given the same input boot time.
Bug: 1016765
Change-Id: I6e4a944a1d58c3916090bab6a4b99573e71a89fc
Reviewed-on: https://chromium-review.googlesource.com/c/crashpad/crashpad/+/1891588
Reviewed-by: Mark Mentovai <mark@chromium.org>
Commit-Queue: Joshua Peraza <jperaza@chromium.org>
