bug#56559: 29.0.50; Invalid CGContextSaveState on NS

[Gerd Möllmann]

Can I please ask another question?  You seem to be the only one here knowing 
the NS stuff.

I'm looking at the ns_focus/ns_unfocus stuff,.  From just eading the code, it 
appears to me that nested calls liek so:

  1 ns_focus          in ns_draw_window_cursor
  2   ns_focus        in draw_.*
  3   ns_unfocus      in draw_.*
  4   ...
  5 ns_unfocus        in ns_draw_window_cursor

are not supported, or is the intention that they are?

My hypthesis is the ns_unfocus in line 3 above undoes the ns_focus from line 1, 
or parts thereof, I haven't checked that thoroughly.

To make that a theory, I've added an ns_focus like so

      ns_focus(f, NULL, 0);
      [NSBezierPath strokeRect:NSInsetRect(r, 0.5, 0.5)];

and voilà the error is gone.