New requirement dictates complex structs must have a defined copy/move
constructors. This CL just fixes the warnings.

R=piman@chromium.org
BUG=582558
CQ_INCLUDE_TRYBOTS=tryserver.chromium.linux:linux_optional_gpu_tests_rel;tryserver.chromium.mac:mac_optional_gpu_tests_rel;tryserver.chromium.win:win_optional_gpu_tests_rel

Review URL: https://codereview.chromium.org/1919443002

Cr-Commit-Position: refs/heads/master@{#389206}