* frame.h (struct frame): Drop resx and resy because the same data is

* frame.h (struct frame): Drop resx and resy because the same data is
available from window system-specific output context.  Adjust users.
(default_pixesls_per_inch_x, default_pixesls_per_inch_y): New
functions to provide defaults when no window system available.
(FRAME_RES_X, FRAME_RES_Y): New macros.
(NUMVAL): Moved from xdisp.c.
* font.c (font_pixel_size, font_find_for_lface, font_open_for_lface)
(Ffont_face_attributes, Fopen_font):
* image.c (gs_load):
* w32font.c (fill_in_logfont):
* xdisp.c (calc_pixel_width_or_height):
* xfaces.c (Fx_family_fonts, set_lface_from_font): Use them.
* xsettings.c (apply_xft_settings): Drop frame loop and adjust comment.