GitLab

This CL also fixes what seems like a bug, where the original code used the
scoped temp dir path before initialization, which meant files were put in the
directory "" (presumably the current working directory).

TBR-ing achuith@, who approved this in
https://codereview.chromium.org/2318023002/ and suggested splitting off into a
separate CL.

TBR=achuith@chromium.org
BUG=640599

Review-Url: https://codereview.chromium.org/2338793004
Cr-Commit-Position: refs/heads/master@{#418535}