Switch SmbFileSystem to use splittable copy methods.

This change transitions SmbFileSystem to using the StartCopy and
ContinueCopy methods so that CopyEntry operations no longer block users
from navigating around during a copy.

Bug: 757625
Change-Id: I9a63e0198b6e529e935fab5f70e8aa95235d2b82
Reviewed-on: https://chromium-review.googlesource.com/1132465
Reviewed-by: Zentaro Kavanagh <zentaro@chromium.org>
Commit-Queue: Bailey Berro <baileyberro@chromium.org>
Cr-Commit-Position: refs/heads/master@{#575284}
1 file changed