Handle pixelwise resize changes in NS port.

Handle pixelwise resize changes in NS port.

* src/nsfns.m (Fx_create_frame): Call change_frame_size twice as per
comment in xfns.c.  Change to pixelwise call.

* src/nsterm.m (x_set_window_size): Change parameters rows/cols to
height/width.  row/cols are locals.
Pass pixelwise to check_frame_size.  Don't set FRAME_PIXEL_WIDTH/HEIGHT.
(updateFrameSize:): Remove gsextra.  Adjust for pixelwise resize.
(windowWillResize): Remove gsextra.  Calculate extra as in
updateFrameSize.
(x_new_font): Don't change frame size if fullscreen.  Change
size pixelwise.