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/+/2898472Reviewed-by: Cody Northrop <cnorthrop@google.com>
Commit-Queue: Ian Elliott <ianelliott@google.com>