Bug fix: Fix --resize-damage

- Fix --resize-damage. I forgot to shrink the painting region back when
  actually copying to destination.

- Include extra pixels around the blur texture to avoid some possible
  small issues, if --resize-damage is positive.

- Known issue: Line artifacts may still appear with --dbe (X Render
  backend) or --glx-swap-method (GLX backend). I doubt if there's way to
  fix this without very inefficient mechanisms.

src/compton.h

@@ -571,7 +571,7 @@ set_tgt_clip(session_t *ps, XserverRegion reg, const reg_data_t *pcache_reg) {
 }
 
 static void
-paint_all(session_t *ps, XserverRegion region, win *t);
+paint_all(session_t *ps, XserverRegion region, XserverRegion region_real, win *t);
 
 static void
 add_damage(session_t *ps, XserverRegion damage);