Fix redundant-move warning from GCC.

Change-Id: I240f2f4c8e1f914d7bcc9625c5fe25a1961593b3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/754701
Auto-Submit: John Stiles <johnstiles@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
Reviewed-by: Nicolette Prevost <nicolettep@google.com>
2 files changed