Separate GrCaps for semaphores and fence syncs.

GrGpu implements CPU/GPU synchronization using GrFence and GPU/GPU
synchronization using GrSemaphore. However, it currently uses one cap,
fenceSyncSupport(), to check for availability of both.

This change separates these caps.

Change-Id: I3e976c7f8e5355c0c212c8de3cc8d8cb77d921d7
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/212720
Reviewed-by: Greg Daniel <egdaniel@google.com>
Reviewed-by: Jim Van Verth <jvanverth@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
10 files changed