Fix SyncID initializer. Requires brace initialization to work on all compilers. Bug: angleproject:8430 Change-Id: I6e79f2446f057bf9eaaaecfc9f82b26320c5ba56 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/5111600 Commit-Queue: Geoff Lang <geofflang@chromium.org> Reviewed-by: Yuly Novikov <ynovikov@chromium.org> Commit-Queue: Yuly Novikov <ynovikov@chromium.org>