Eliminate mojo::Shell client lib class

mash/wm/non_client_frame_controller.h

Index: mash/wm/non_client_frame_controller.h
diff --git a/mash/wm/non_client_frame_controller.h b/mash/wm/non_client_frame_controller.h
index b5346f25e5e599ed964f6aad778a27836137273f..c43cf736ffb631a5365744d18e5eaaa12aec06ea 100644
--- a/mash/wm/non_client_frame_controller.h
+++ b/mash/wm/non_client_frame_controller.h
@@ -17,7 +17,7 @@ class Insets;
 }
 
 namespace mojo {
-class Shell;
+class Connector;
 }
 
 namespace mus {
@@ -33,7 +33,7 @@ class NonClientFrameController : public views::WidgetDelegateView,
                                  public mus::WindowObserver {
  public:
   // NonClientFrameController deletes itself when |window| is destroyed.
-  NonClientFrameController(mojo::Shell* shell,
+  NonClientFrameController(mojo::Connector* connector,
                            mus::Window* window,
                            mus::WindowManagerClient* window_manager_client);