Removes code using mus client lib

ui/views/mus/test_utils.h

Index: ui/views/mus/test_utils.h
diff --git a/ui/views/mus/test_utils.h b/ui/views/mus/test_utils.h
index c4d21ee8a424e212d2905357ba45895983696c63..419fee9dc31436089e6bbb7553d420b8f53b9cb1 100644
--- a/ui/views/mus/test_utils.h
+++ b/ui/views/mus/test_utils.h
@@ -7,29 +7,10 @@
 
 #include "base/memory/ptr_util.h"
 #include "ui/views/mus/mus_client.h"
-#include "ui/views/mus/window_manager_connection.h"
 
 namespace views {
 namespace test {
 
-class WindowManagerConnectionTestApi {
- public:
-  explicit WindowManagerConnectionTestApi(WindowManagerConnection* connection)
-      : connection_(connection) {}
-  ~WindowManagerConnectionTestApi() {}
-
-  ui::Window* GetUiWindowAtScreenPoint(const gfx::Point& point) {
-    return connection_->GetUiWindowAtScreenPoint(point);
-  }
-
-  ScreenMus* screen() { return connection_->screen_.get(); }
-
- private:
-  WindowManagerConnection* connection_;
-
-  DISALLOW_COPY_AND_ASSIGN(WindowManagerConnectionTestApi);
-};
-
 class MusClientTestApi {
  public:
   static std::unique_ptr<MusClient> Create(