(Vwindow_system): Declared.

(Vwindow_system): Declared.
(win32_fill_rect, dumpglyphs, do_line_dance, x_draw_box):
Use Get/ReleaseFrameDC.

(pixel_to_glyph_coords): Support tty mode.
(w32_read_socket): Explicitly use FALSE.
Handle WM_PALLETTECHANGED event.
(parse_button): Handle mouse button emulation.

(my_show_window, my_set_window_pos): New functions.
(x_set_offset, x_set_window_size, x_raise_frame, x_lower_frame):
Use my_set_window_pos.
(x_make_frame_visible, x_iconify_frame): Use my_show_window.

(x_draw_box): Don't trim right and bottom.
(x_make_frame_visible): Don't invoke SetForgroundWindow.

(win32_term_init): Use GetDC directly.  Initialize palette
and win32_num_mouse_buttons.
(win32_update_begin): Regenerate palette if necessary.
(x_delete_display): Free palette.

(win32_initialize) [ATTACH_THREADS]: Only AttachThreadInput if
conditional is defined.