Add Safari versions for EXT_frag_depth API (#18013)
Add Safari versions for EXT_frag_depth API (#18013)

This PR adds real values for Safari (Desktop and iOS/iPadOS) for the `EXT_frag_depth` API, based upon results from the [mdn-bcd-collector](https://mdn-bcd-collector.appspot.com) project (v6.2.6).

Tests Used: https://mdn-bcd-collector.appspot.com/tests/api/EXT_frag_depth

_Check out the [collector's guide on how to review this PR](https://github.com/foolip/mdn-bcd-collector#reviewing-bcd-changes)._
mdn/browser-compat-data,mdn/browser-compat-data,chrisdavidmills/browser-compat-data,chrisdavidmills/browser-compat-data