Revert of Converts chrome to aura-mus

chrome/browser/ui/views/frame/browser_non_client_frame_view_mus.h

Index: chrome/browser/ui/views/frame/browser_non_client_frame_view_mus.h
diff --git a/chrome/browser/ui/views/frame/browser_non_client_frame_view_mus.h b/chrome/browser/ui/views/frame/browser_non_client_frame_view_mus.h
index bdd84f790a5d53e2b0c9d783b00dc3ea49bfb2bf..48b4bc43146f38445054fd59760c91f5f1344254 100644
--- a/chrome/browser/ui/views/frame/browser_non_client_frame_view_mus.h
+++ b/chrome/browser/ui/views/frame/browser_non_client_frame_view_mus.h
@@ -19,6 +19,10 @@
 
 class TabIconView;
 class WebAppLeftHeaderView;
+
+namespace ui {
+class Window;
+}
 
 class BrowserNonClientFrameViewMus : public BrowserNonClientFrameView,
                                      public TabIconViewModel,
@@ -68,7 +72,9 @@
   void UpdateProfileIcons() override;
 
  private:
-  // Resets the client area of the WindowTreeHostMus.
+  ui::Window* mus_window();
+
+  // Resets the client area on the ui::Window.
   void UpdateClientArea();
 
   // TabStripObserver: