Implement the EGL_KHR_fence_sync in libagl

Implementing this in libagl allows us to start using it for
SurfaceTexture in emulator builds, which is necessary to avoid
corruption in the Browser when using the host-accelerated GL path.

Bug: 6515813
Change-Id: Icafba8687cb5d010d8d42b3866b298d2be984fc9
2 files changed