Adds additional_client_area to client area

ui/aura/mus/window_tree_host_mus.h

Index: ui/aura/mus/window_tree_host_mus.h
diff --git a/ui/aura/mus/window_tree_host_mus.h b/ui/aura/mus/window_tree_host_mus.h
index 4cf6f1b9331f295018d2532aee4fb5973c347376..0d923b46d86668c8058198d6611c9a7e52faab0e 100644
--- a/ui/aura/mus/window_tree_host_mus.h
+++ b/ui/aura/mus/window_tree_host_mus.h
@@ -61,7 +61,8 @@ class AURA_EXPORT WindowTreeHostMus : public aura::WindowTreeHostPlatform {
   InputMethodMus* input_method() { return input_method_.get(); }
 
   // Sets the client area on the underlying mus window.
-  void SetClientArea(const gfx::Insets& insets);
+  void SetClientArea(const gfx::Insets& insets,
+                     const std::vector<gfx::Rect>& additional_client_area);
 
   // Sets the hit test mask on the underlying mus window. Pass base::nullopt to
   // clear.