Revert of IME for Mus: Make InputMethodMus use the IME Mojo API.

ui/views/mus/window_tree_host_mus.h

Index: ui/views/mus/window_tree_host_mus.h
diff --git a/ui/views/mus/window_tree_host_mus.h b/ui/views/mus/window_tree_host_mus.h
index a606553260663648ea91c8a8b56dee70398b92e5..fa096fcadd8cc0f52a121292d877ed508adc1d6b 100644
--- a/ui/views/mus/window_tree_host_mus.h
+++ b/ui/views/mus/window_tree_host_mus.h
@@ -6,7 +6,6 @@
 #define UI_VIEWS_MUS_WINDOW_TREE_HOST_MUS_H_
 
 #include "base/macros.h"
-#include "services/shell/public/cpp/connector.h"
 #include "ui/aura/window_tree_host_platform.h"
 #include "ui/views/mus/mus_export.h"
 
@@ -22,7 +21,7 @@
 
 namespace views {
 
-class InputMethodMus;
+class InputMethodMUS;
 class NativeWidgetMus;
 class PlatformWindowMus;
 
@@ -32,8 +31,6 @@
   ~WindowTreeHostMus() override;
   NativeWidgetMus* native_widget() { return native_widget_; }
 
-  void InitInputMethod(shell::Connector* connector);
-
  private:
   // aura::WindowTreeHostPlatform:
   void DispatchEvent(ui::Event* event) override;
@@ -42,7 +39,7 @@
   void OnCloseRequest() override;
 
   NativeWidgetMus* native_widget_;
-  std::unique_ptr<InputMethodMus> input_method_;
+  std::unique_ptr<InputMethodMUS> input_method_;
 
   DISALLOW_COPY_AND_ASSIGN(WindowTreeHostMus);
 };