Reset binding offset & size when unbinding Bug: angleproject:4147 Change-Id: I4ace1221d32631cdb14a95c71ee9a1617837a5ea Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1970495 Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org> Reviewed-by: Tobin Ehlis <tobine@google.com> Commit-Queue: Courtney Goeltzenleuchter <courtneygo@google.com>