Immediate clear to black on Windows was not working, fixed.

Author: Trent Gamblin

src/win/wwindow.c

@@ -177,8 +177,6 @@ HWND _al_win_create_window(ALLEGRO_DISPLAY *display, int width, int height, int
       NULL,NULL,window_class.hInstance,0);
    al_free(window_title);
 
-   clear_window(my_window, width, height);
-
    if (_al_win_register_touch_window)
       _al_win_register_touch_window(my_window, 0);
 
@@ -205,6 +203,8 @@ HWND _al_win_create_window(ALLEGRO_DISPLAY *display, int width, int height, int
 
    ShowWindow(my_window, SW_SHOW);
 
+   clear_window(my_window, width, height);
+
    if (!(flags & ALLEGRO_RESIZABLE) && !(flags & ALLEGRO_FULLSCREEN)) {
       /* Make the window non-resizable */
       HMENU menu;
@@ -245,8 +245,6 @@ HWND _al_win_create_faux_fullscreen_window(LPCTSTR devname, ALLEGRO_DISPLAY *dis
       NULL,NULL,window_class.hInstance,0);
    al_free(window_title);
 
-   clear_window(my_window, width, height);
-
    if (_al_win_register_touch_window)
       _al_win_register_touch_window(my_window, 0);
 
@@ -271,6 +269,8 @@ HWND _al_win_create_faux_fullscreen_window(LPCTSTR devname, ALLEGRO_DISPLAY *dis
 
    ChangeDisplaySettingsEx(devname, &mode, NULL, 0, NULL/*CDS_FULLSCREEN*/);
 
+   clear_window(my_window, width, height);
+
    return my_window;
 }
 
@@ -1236,9 +1236,13 @@ bool _al_win_set_display_flag(ALLEGRO_DISPLAY *display, int flag, bool onoff)
                win_display->window, HWND_TOP, pos_x-bw/2, pos_y-bh/2, 0, 0, SWP_NOSIZE
             );
          }
+
          // Show the window again
          SetWindowPos(win_display->window, 0, 0, 0, 0, 0, SWP_SHOWWINDOW | SWP_NOSIZE | SWP_NOZORDER | SWP_NOMOVE);
 
+         // Clear the window to black
+         clear_window(win_display->window, display->w, display->h);
+
          ASSERT(!!(display->flags & ALLEGRO_FULLSCREEN_WINDOW) == onoff);
          return true;
       case ALLEGRO_MAXIMIZED: