Fix many return-std-move-in-c++11 warnings

Change-Id: Ib0042cf412fe3c5fa600b7ae644d16740457535e
Reviewed-on: https://skia-review.googlesource.com/121354
Commit-Queue: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Mike Klein <mtklein@google.com>
Auto-Submit: Kevin Lubick <kjlubick@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
9 files changed