Move shell service to toplevel shell namespace

ui/views/mus/native_widget_mus.h

Index: ui/views/mus/native_widget_mus.h
diff --git a/ui/views/mus/native_widget_mus.h b/ui/views/mus/native_widget_mus.h
index 60a2d23449e29ffcfecdd7c45a79019f465694be..8a7ed8ceb0bd7fc20de9a7f7ee5610795b88b56a 100644
--- a/ui/views/mus/native_widget_mus.h
+++ b/ui/views/mus/native_widget_mus.h
@@ -29,15 +29,15 @@ class WindowTreeClient;
 class Window;
 }
 
-namespace mojo {
-class Connector;
-}
-
 namespace mus {
 class Window;
 class WindowTreeConnection;
 }
 
+namespace shell {
+class Connector;
+}
+
 namespace wm {
 class FocusController;
 }
@@ -58,7 +58,7 @@ class VIEWS_MUS_EXPORT NativeWidgetMus : public internal::NativeWidgetPrivate,
                                          public aura::WindowTreeHostObserver {
  public:
   NativeWidgetMus(internal::NativeWidgetDelegate* delegate,
-                  mojo::Connector* connector,
+                  shell::Connector* connector,
                   mus::Window* window,
                   mus::mojom::SurfaceType surface_type);
   ~NativeWidgetMus() override;