Fix regression due to https://codereview.chromium.org/757863002

The intent of https://codereview.chromium.org/757863002 was to make whether an
aura::Window's layer has a NULL delegate not affect the aura::Window stacking
order. This CL removes the logic that I forgot to remove in the initial CL.

BUG=443433
TEST=TransientWindowStackingClientTest.StackAboveClosingWindow

Review URL: https://codereview.chromium.org/850553003

Cr-Commit-Position: refs/heads/master@{#311163}

2 files changed, 15 insertions, 6 deletions

diff --git a/ui/wm/core/transient_window_stacking_client.cc b/ui/wm/core/transient_window_stacking_client.cc
index 740fe99..9be72b6 100644
--- a/ui/wm/core/transient_window_stacking_client.cc
+++ b/ui/wm/core/transient_window_stacking_client.cc
@@ -94,12 +94,6 @@ bool TransientWindowStackingClient::AdjustStacking(
     *target = siblings[target_i];
   }
 
-  // If we couldn't find a valid target position, don't move anything.
-  if (*direction == Window::STACK_ABOVE &&
-      ((*target)->layer() && (*target)->layer()->delegate() == NULL)) {
-    return false;
-  }
-
   return *child != *target;
 }
 
diff --git a/ui/wm/core/transient_window_stacking_client_unittest.cc b/ui/wm/core/transient_window_stacking_client_unittest.cc
index 7b8c127..5e37cf4 100644
--- a/ui/wm/core/transient_window_stacking_client_unittest.cc
+++ b/ui/wm/core/transient_window_stacking_client_unittest.cc
@@ -174,4 +174,19 @@ TEST_F(TransientWindowStackingClientTest, TransientChildrenGroupBelow) {
   EXPECT_EQ("2 22 21 213 211 212 1 11", ChildWindowIDsAsString(parent.get()));
 }
 
+// Tests that windows can be stacked above windows with a NULL layer delegate.
+// Windows have a NULL layer delegate when they are in the process of closing.
+// See crbug.com/443433
+TEST_F(TransientWindowStackingClientTest,
+       StackAboveWindowWithNULLLayerDelegate) {
+  scoped_ptr<Window> parent(CreateTestWindowWithId(0, root_window()));
+  scoped_ptr<Window> w1(CreateTestWindowWithId(1, parent.get()));
+  scoped_ptr<Window> w2(CreateTestWindowWithId(2, parent.get()));
+  w2->layer()->set_delegate(NULL);
+  EXPECT_EQ(w2.get(), parent->children().back());
+
+  parent->StackChildAbove(w1.get(), w2.get());
+  EXPECT_EQ(w1.get(), parent->children().back());
+}
+
 }  // namespace wm