Eliminate mojo::Shell client lib class

mash/screenlock/screenlock.h

Index: mash/screenlock/screenlock.h
diff --git a/mash/screenlock/screenlock.h b/mash/screenlock/screenlock.h
index e05a46cb0e9983f07d84d7cca5e3d5e09f26d5b4..e87995f805b79e6386869e5ad5c38874c4a22557 100644
--- a/mash/screenlock/screenlock.h
+++ b/mash/screenlock/screenlock.h
@@ -29,13 +29,12 @@ class Screenlock : public mojo::ShellClient,
 
  private:
   // mojo::ShellClient:
-  void Initialize(mojo::Shell* shell, const std::string& url,
+  void Initialize(mojo::Connector* connector, const std::string& url,
                   uint32_t id, uint32_t user_id) override;
 
   // mash::shell::mojom::ScreenlockStateListener:
   void ScreenlockStateChanged(bool locked) override;
 
-  mojo::Shell* shell_;
   mojo::TracingImpl tracing_;
   scoped_ptr<views::AuraInit> aura_init_;
   mojo::BindingSet<mash::shell::mojom::ScreenlockStateListener> bindings_;