GitLab

PushDataDeps takes a long time even when all files are on the device
because calculating the digests of all the files takes _much_ longer
on a device than it does on a host.

Skipping the push step during test listing -- where the data deps are
unnecessary -- means that we don't try to push files twice in each
gtest run, so we skip all of the device-side MD5 calculations that
would happen in the second run.

BUG=400440

Review URL: https://codereview.chromium.org/560133002

Cr-Commit-Position: refs/heads/master@{#294667}