Implementation of EGL_KHR_fence_sync.

Bug 21662268

Change-Id: Iefdc18303c42967ccc25fd6580851e05520dc2b9
Reviewed-on: https://swiftshader-review.googlesource.com/4071
Tested-by: Nicolas Capens <capn@google.com>
Reviewed-by: Alexis Hétu <sugoi@google.com>
Reviewed-by: Nicolas Capens <capn@google.com>
12 files changed