DialogClientView: Correct the order in which subviews are focused.

ui/views/window/client_view.cc

Index: ui/views/window/client_view.cc
diff --git a/ui/views/window/client_view.cc b/ui/views/window/client_view.cc
index fb7d89fed1823b670feb600d00685f1e83f4526a..7a87d8decde0cc8404e71d0af44113136966ed84 100644
--- a/ui/views/window/client_view.cc
+++ b/ui/views/window/client_view.cc
@@ -92,6 +92,8 @@ void ClientView::ViewHierarchyChanged(
     // Insert |contents_view_| at index 0 so it is first in the focus chain.
     // (the OK/Cancel buttons are inserted before contents_view_)
     AddChildViewAt(contents_view_, 0);
+  } else if (!details.is_add && details.child == contents_view_) {
+    contents_view_ = nullptr;
   }
 }