Add drive label to be accessible from volume info.

Drive label, e.g. "SanDisk 3.0", is required to appear as the label of
the root entry for a partitioned external media device in the directory
tree.

Bug: 918795
Change-Id: I734a9995bd7ebbc249702b5a11fd5f163332f9dd
Reviewed-on: https://chromium-review.googlesource.com/c/1426238
Commit-Queue: Noel Gordon <noel@chromium.org>
Reviewed-by: Noel Gordon <noel@chromium.org>
Reviewed-by: Anand Mistry <amistry@chromium.org>
Reviewed-by: Luciano Pacheco <lucmult@chromium.org>
Cr-Commit-Position: refs/heads/master@{#625614}
14 files changed