SPIGOT-1968: Use correct explosion yield

nms-patches/Explosion.patch

@@ -90,13 +90,13 @@
 +            float yield;
 +
 +            if (explode != null) {
-+                EntityExplodeEvent event = new EntityExplodeEvent(explode, location, blockList, 0.3F);
++                EntityExplodeEvent event = new EntityExplodeEvent(explode, location, blockList, 1.0F / this.size);
 +                this.world.getServer().getPluginManager().callEvent(event);
 +                cancelled = event.isCancelled();
 +                bukkitBlocks = event.blockList();
 +                yield = event.getYield();
 +            } else {
-+                BlockExplodeEvent event = new BlockExplodeEvent(location.getBlock(), blockList, 0.3F);
++                BlockExplodeEvent event = new BlockExplodeEvent(location.getBlock(), blockList, 1.0F / this.size);
 +                this.world.getServer().getPluginManager().callEvent(event);
 +                cancelled = event.isCancelled();
 +                bukkitBlocks = event.blockList();