toolchain-utils: fix unused-argument lint warnings.

BUG=chromium:570458
TEST='crosperf/run_tests.sh' passes.

Change-Id: Iae6add81a1fb1c929a09808b5870d2a1762ef291
Reviewed-on: https://chrome-internal-review.googlesource.com/243413
Commit-Ready: Rahul Chaudhry <rahulchaudhry@google.com>
Tested-by: Rahul Chaudhry <rahulchaudhry@google.com>
Reviewed-by: Caroline Tice <cmtice@google.com>
4 files changed