Fixed blocks (e.g. sugar canes) adjacent to physics blocks (e.g. sand) not updating.

Fixes WORLDGUARD-3367. This change MAY have breaking unintended consequences,
but the physics configs seem to still be working.

src/main/java/com/sk89q/worldguard/bukkit/listener/WorldGuardBlockListener.java

@@ -380,7 +380,7 @@ public void onBlockPhysics(BlockPhysicsEvent event) {
             return;
         }
 
-        int id = event.getChangedTypeId();
+        int id = event.getBlock().getTypeId();
 
         if (id == 13 && wcfg.noPhysicsGravel) {
             event.setCancelled(true);