Fix GrGLSync definition

By fixing this some ugly casts are avoided in setting up Chrome's GrGLInterface

Change-Id: Ie540fc41b3cbb27f976d784cad90ae10c2cef9ed
Reviewed-on: https://skia-review.googlesource.com/12621
Reviewed-by: Brian Salomon <bsalomon@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
1 file changed