### Feature request

`customButtonsOnHover` fixes a lot of issues with drag and `pointer` styles, but my app currently uses `hidden-inset` so this setting changes the position of the buttons. I'd suggest `customButtonsOnHover` either be an option outside of `titleBarStyle` that respects `titleBarStyle`s values ('hiddenInset' or `hidden') or the addition of a `customButtonsOnHoverInset`.

As a separate note, the docs for `customButtonsOnHover` currently specify it's a Boolean type, but it's a string value.
shell/browser/native_window.h
bool transparent_ = false;
  
  extensions::SizeConstraints size_constraints_;
  
  bool enable_larger_than_screen_ = false;
  
  bool is_closed_ = false;
  
  
  double sheet_offset_x_ = 0.0;
  double sheet_offset_y_ = 0.0;
  
  
  double aspect_ratio_ = 0.0;
  gfx::Size aspect_ratio_extraSize_;
  
  NativeWindow* parent_ = nullptr;
  
  bool is_modal_ = false;
  
  std::list<NativeBrowserView*> browser_views_;
  
  base::ObserverList<NativeWindowObserver> observers_;
  
  base::string16 accessible_title_;
  base::WeakPtrFactory<NativeWindow> weak_factory_;
  DISALLOW_COPY_AND_ASSIGN(NativeWindow);
};
class NativeWindowRelay