Merged a cleaned up version of Jiang's code changes from Google Summer of Code 2009

--HG--
extra : convert_revision : svn%3Ac70aab31-4412-0410-b14c-859654838e24/trunk%403823

src/video/SDL_sysvideo.h

@@ -277,6 +277,11 @@ struct SDL_VideoDevice
     /* Suspend the screensaver */
     void (*SuspendScreenSaver) (_THIS);
 
+    /* Text input */
+    void (*StartTextInput) (_THIS);
+    void (*StopTextInput) (_THIS);
+    void (*SetTextInputRect) (_THIS, SDL_Rect *rect);
+
     /* * * */
     /* Data common to all drivers */
     SDL_bool suspend_screensaver;