Add capture functions for desktop GL entry points The parameter capture functions are left unimplemented for now. Bug: angleproject:7533 Change-Id: Ief356e7401805cf9b417e1f5cc3790011237e03f Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3858618 Reviewed-by: Jamie Madill <jmadill@chromium.org> Reviewed-by: Cody Northrop <cnorthrop@google.com> Commit-Queue: Eddie Hatfield <eddiehatfield@google.com>