GitLab

This reverts commit f19a4c81.

Reason for revert:

Breaks https://ci.chromium.org/p/chromium/builders/luci.chromium.ci/linux-chromeos-dbg

Sample failure line:
[ RUN      ] AppMenuModelTest.Basics
[31511:31511:0513/150125.044037:3461088700:FATAL:window.cc(91)] Check failed: env || !g_env_arg_required_string. Within ash you must supply a non-null aura::Env when creating a Window, use window_factory, or supply the Env obtained from Shell::Get()->aura_env()

Causes ~1000 tests to fail.

Original change's description:
> views: random cleanup from removing support for mus
> 
> This functionality was added purely for mus and is no longer necessary.
> 
> BUG=958241
> TEST=purely dead code removal
> 
> Change-Id: I856576f9adef9728d837d56e82f94a87aeea040b
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1610497
> Commit-Queue: Scott Violet <sky@chromium.org>
> Reviewed-by: Evan Stade <estade@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#659207}

TBR=sky@chromium.org,estade@chromium.org

Change-Id: I7bbf97863986000679890e2076dbb2b0e5fdaf46
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 958241
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1610709Reviewed-by: Avi Drissman <avi@chromium.org>
Commit-Queue: Avi Drissman <avi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#659498}