[Autotest] Correct version check for chrome-perf build.

Code is changed in check_version_to_confirm_install, so that special logic is
only applied to trybot paladin build. For any other build, the version without
any tail part (e.g., -rc#) is used to match the version in lsb-release.

BUG=chromium:230375
TEST=local unit test, run_suite with lumpy-chrome-perf/R28-3970.0.0-b2996
DEPLOY=none

Change-Id: I0283546a0b1d7f1036240bb6062d37b54ca53120
Reviewed-on: https://gerrit.chromium.org/gerrit/48016
Reviewed-by: Richard Barnette <jrbarnette@chromium.org>
Commit-Queue: Dan Shi <dshi@chromium.org>
Reviewed-by: Dan Shi <dshi@chromium.org>
Tested-by: Dan Shi <dshi@chromium.org>
2 files changed