Vulkan: Fix AGI hierarchy The GLES hierarchy of debug-util markers given to AGI was wrong for several games. The problem is that glDrawBuffer* was treated as a draw call, instead of as the state-setting call that it is. Bug: b/184888395 Change-Id: I6911bd3aae42b5f29b3f40466a615c614651ca8a Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2898472 Reviewed-by: Cody Northrop <cnorthrop@google.com> Commit-Queue: Ian Elliott <ianelliott@google.com>