This reverts commit 0c01e367.

Reason for revert: Its dependency that was reverted has now relanded:

    https://chromium-review.googlesource.com/c/angle/angle/+/1489153

Original change's description:
> Revert "Vulkan: Implement debug markers"
>
> This reverts commit 983e4469.
>
> Reason for revert: Depends on a CL that's reverted: https://chromium-review.googlesource.com/c/angle/angle/+/1470605
>
> Original change's description:
> > Vulkan: Implement debug markers
> >
> > Covers both GL_KHR_debug and GL_EXT_debug_marker.
> >
> > Debug markers are used to specify events or hierarchically categorize a
> > set of commands within the command buffer.  When debugging, this allows
> > for quicker navigation to the draw calls of interest, and otherwise
> > provides context to debug output.
> >
> > Bug: angleproject:2853
> > Change-Id: Id65e11fc877d9e70b6fd0fae7f0bbbcb1164bf10
> > Reviewed-on: https://chromium-review.googlesource.com/c/1403956
> > Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
> > Reviewed-by: Jamie Madill <jmadill@chromium.org>
> > Reviewed-by: Geoff Lang <geofflang@chromium.org>
>
> TBR=geofflang@chromium.org,jmadill@chromium.org,syoussefi@chromium.org
>
> Change-Id: I7fcfc8683195d396aec61848719f52c0fa049ece
> No-Presubmit: true
> No-Tree-Checks: true
> No-Try: true
> Bug: angleproject:2853
> Reviewed-on: https://chromium-review.googlesource.com/c/1470606
> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>

TBR=geofflang@chromium.org,jmadill@google.com,syoussefi@chromium.org

Bug: angleproject:2853
Change-Id: Ie19ae103244d54dcf7108d5f61c24e318fc44057
Reviewed-on: https://chromium-review.googlesource.com/c/1489154
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Reviewed-by: Jamie Madill <jmadill@google.com>