logging_CrashSender: rework to handle new locking system

The crash_sender logic uses flock now to guarantee locking between runs
rather than the old pid file management.  Update the autotests to handle
that method so we can delete the old pid heuristic.

BUG=chromium:199491
TEST=`cbuildbot x86-generic-full` works
CQ-DEPEND=CL:169486

Change-Id: I563b619d44cc2c426807fcedd24332a3c14acccf
Reviewed-on: https://chromium-review.googlesource.com/201495
Reviewed-by: Ben Chan <benchan@chromium.org>
Tested-by: Mike Frysinger <vapier@chromium.org>
Commit-Queue: Mike Frysinger <vapier@chromium.org>
2 files changed