GitLab

The device list header should be "Available devices" instead of
"Available devices will appear here." when there already is one or more
devices in the external storage list.

Bug: 1007202
Test: Manual test
Change-Id: Ib08103236d32ada77b8328f29eacb1ed0a6a7759
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1895252Reviewed-by: Hector Carmona <hcarmona@chromium.org>
Commit-Queue: Naoki Fukino <fukino@chromium.org>
Cr-Commit-Position: refs/heads/master@{#712877}