Treat LeavesDecayEvent as canceled if a plugin changes the block

nms-patches/BlockLeaves.patch

@@ -1,5 +1,5 @@
---- ../work/decompile-8eb82bde//net/minecraft/server/BlockLeaves.java	2014-11-28 17:43:42.913707439 +0000
-+++ src/main/java/net/minecraft/server/BlockLeaves.java	2014-11-28 17:38:22.000000000 +0000
+--- ../work/decompile-8eb82bde//net/minecraft/server/BlockLeaves.java	2014-11-29 22:31:45.788917956 +0000
++++ src/main/java/net/minecraft/server/BlockLeaves.java	2014-11-29 22:27:58.604922998 +0000
 @@ -2,6 +2,8 @@
  
  import java.util.Random;
@@ -17,7 +17,7 @@
 +        LeavesDecayEvent event = new LeavesDecayEvent(world.getWorld().getBlockAt(blockposition.getX(), blockposition.getY(), blockposition.getZ()));
 +        world.getServer().getPluginManager().callEvent(event);
 +
-+        if (event.isCancelled()) {
++        if (event.isCancelled() || world.getType(blockposition).getBlock() != this) {
 +            return;
 +        }
 +        // CraftBukkit end