Poke window managers to get them to respect the resize hints.

src/video/x11/SDL_x11window.c

@@ -758,6 +758,36 @@ X11_SetWindowSize(_THIS, SDL_Window * window)
          XSetWMNormalHints(display, data->xwindow, sizehints);
 
          XFree(sizehints);
+
+        /* From Pierre-Loup:
+           For the windowed resize problem; WMs each have their little quirks with
+           that.  When you change the size hints, they get a ConfigureNotify event
+           with the WM_NORMAL_SIZE_HINTS Atom.  They all save the hints then, but
+           they don't all resize the window right away to enforce the new hints.
+           Those who do properly do it are:
+          
+             - XFWM
+             - metacity
+             - KWin
+
+           These are great.  Now, others are more problematic as you could observe
+           first hand.  Compiz/Unity only falls into the code that does it on select
+           actions, such as window move, raise, map, etc.
+
+           WindowMaker is even more difficult and will _only_ do it on map.
+
+           Awesome only does it on user-initiated moves as far as I can tell.
+          
+           Your raise workaround only fixes compiz/Unity.  With that all "modern"
+           window managers are covered.  Trying to Hide/Show on windowed resize
+           (UnMap/Map) fixes both Unity and WindowMaker, but introduces subtle
+           problems with transitioning from Windowed to Fullscreen on Unity.  Since
+           some window moves happen after the transitions to fullscreen, that forces
+           SDL to fall from windowed to fullscreen repeatedly and it sometimes leaves
+           itself in a state where the fullscreen window is slightly offset by what
+           used to be the window decoration titlebar.
+        */
+        XRaiseWindow(display, data->xwindow);
     } else {
         XResizeWindow(display, data->xwindow, window->w, window->h);
     }