GitLab

The test delegate should now return a valid temp
directory for the user's downloads dir.

BUG=none
TEST=Existing tests

Change-Id: I159690b0d3bc330e473c33b52f5057cb823a7363
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2587550Reviewed-by: Xiaoqian Dai <xdai@chromium.org>
Commit-Queue: Ahmed Fakhry <afakhry@chromium.org>
Cr-Commit-Position: refs/heads/master@{#836267}