This makes sure the metadata is found during minimization. Also renames
the test files to fit the naming pattern.

BUG=chromium:673246
NOTRY=true
TBR=tandrii@chromium.org,mbarbella@chromium.org

Review-Url: https://codereview.chromium.org/2622653002
Cr-Commit-Position: refs/heads/master@{#42150}