Suppress new warning -Wreturn-std-move on clang tot bots.

TBR=hans@chromium.org

Bug: 832211
Change-Id: I48e93524b532b33430219ccfb9758e940238a43a
Reviewed-on: https://chromium-review.googlesource.com/1010533
Reviewed-by: Nico Weber <thakis@chromium.org>
Commit-Queue: Nico Weber <thakis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550366}
1 file changed