Removes unnecessary views::Widget::InitParams::top_level

ui/views/widget/widget.h

Index: ui/views/widget/widget.h
diff --git a/ui/views/widget/widget.h b/ui/views/widget/widget.h
index 6bdf589a58a408698eedc59bcfc8a2fd1ca193d4..17e124773e206dbc2f8dcf7aabda35ff55cafea2 100644
--- a/ui/views/widget/widget.h
+++ b/ui/views/widget/widget.h
@@ -235,10 +235,6 @@ class VIEWS_EXPORT Widget : public internal::NativeWidgetDelegate,
     // TODO(beng): Figure out if there's a better way to expose this, e.g. get
     // rid of NW subclasses and do this all via message handling.
     DesktopWindowTreeHost* desktop_window_tree_host;
-    // Whether this window is intended to be a toplevel window with no
-    // attachment to any other window. (This may be a transient window if
-    // |parent| is set.)
-    bool top_level;
     // Only used by NativeWidgetAura. Specifies the type of layer for the
     // aura::Window. Default is WINDOW_LAYER_TEXTURED.
     aura::WindowLayerType layer_type;