Revert "views: changes test to not use equality"

This reverts commit 72a83a6c2276e5afcec4f87f2edad760a4809a20.

Reason for revert: The text failure was fixed at https://chromium-review.googlesource.com/c/chromium/src/+/1168466 . The failure was a side effect of my change and a lingering issue, so reverting the revert.

Original change's description:
> views: changes test to not use equality
> 
> This test was assuming a newly created Window got a pointer value different
> than one recently destroyed. For whatever reason my recent patch made it more
> likely (on the msan bot) that the newly created pointer got the same value as
> the one destroyed, leading to failure.
> 
> I'm converting the test to verify the window is destroyed using a WindowTracker.
> 
> BUG=847992
> TEST=covered by tests
> 
> Change-Id: I4f9f64ad59ae15b0314619a93935d7e85bb6d8e7
> Reviewed-on: https://chromium-review.googlesource.com/1168466
> Reviewed-by: Michael Wasserman <msw@chromium.org>
> Commit-Queue: Scott Violet <sky@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#581788}

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

Change-Id: I902ae7e85e8a40e5d682a332b2a7171eb233c300
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 847992
Reviewed-on: https://chromium-review.googlesource.com/1168762
Reviewed-by: Scott Violet <sky@chromium.org>
Commit-Queue: Scott Violet <sky@chromium.org>
Cr-Commit-Position: refs/heads/master@{#581791}
diff --git a/ui/views/mus/remote_view/remote_view_provider_unittest.cc b/ui/views/mus/remote_view/remote_view_provider_unittest.cc
index bf3a202d..f87a320 100644
--- a/ui/views/mus/remote_view/remote_view_provider_unittest.cc
+++ b/ui/views/mus/remote_view/remote_view_provider_unittest.cc
@@ -14,7 +14,6 @@
 #include "ui/aura/test/aura_test_base.h"
 #include "ui/aura/test/mus/test_window_tree.h"
 #include "ui/aura/window.h"
-#include "ui/aura/window_tracker.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/views/mus/remote_view/remote_view_provider_test_api.h"
 
@@ -160,15 +159,11 @@
   aura::Window* embedder = SimulateEmbed();
   ASSERT_TRUE(embedder);
 
-  aura::WindowTracker window_tracker;
-  window_tracker.Add(embedder);
   SimulateEmbedderClose(embedder);
-  // SimulateEmbedderClose() should delete |embedder|.
-  EXPECT_TRUE(window_tracker.windows().empty());
 
   aura::Window* new_embedder = SimulateEmbed();
-  // SimulateEmbed() should create a new window.
   ASSERT_TRUE(new_embedder);
+  EXPECT_NE(new_embedder, embedder);
 }
 
 }  // namespace views