Add CanEntityDestroyBlockEvent

Hey there,

Ok I'm posting this here bacause I don't have the knowledge to use github pull req.

I'd like to add a CanEntityDestroyBlockEvent that is like an event based version of the block.canEntityDestroy.

Reason for this is that there is currently no good way to e.g. cancel/allow the destruction from the EnderDragon.

Here is my example how to implement that:

The event itself:

package net.minecraftforge.event.entity;

import net.minecraft.block.state.IBlockState;
import net.minecraft.entity.Entity;
import net.minecraft.util.BlockPos;
import net.minecraft.world.World;
import net.minecraftforge.event.world.BlockEvent;

public class CanEntityDestroyBlockEvent extends BlockEvent
{
    public final Entity entity;

    public Result canDestroy = Result.DEFAULT;

    public CanEntityDestroyBlockEvent(World world, BlockPos pos, IBlockState state, Entity entity)
    {
        super(world, pos, state);

        this.entity = entity;
    }
}

The additional method for the world class:

    public boolean canEntityDestroyBlock(BlockPos pos, IBlockState state, Entity entity)
    {
        CanEntityDestroyBlockEvent event = new CanEntityDestroyBlockEvent(this, pos, state, entity);
        MinecraftForge.EVENT_BUS.post(event);
        
        switch (event.canDestroy)
        {
            case ALLOW:
                return true;
            case DENY:
                return false;
            default:
                return state.getBlock().canEntityDestroy(this, pos, entity);
        }
    }

The method block.canEntityDestroy is only used by EntityDragon and EntityWither so we have to change them too:

EntityDragon: method destroyBlocksInAABB and modify line 527 to:

if (worldObj.canEntityDestroyBlock(new BlockPos(k1, l1, i2), this) && this.worldObj.getGameRules().getGameRuleBooleanValue("mobGriefing"))

EntityWither: method updateAITasks and modify line 375 to:

if (!block.isAir(worldObj, new BlockPos(j2, k, l)) && worldObj.canEntityDestroyBlock(new BlockPos(j2, k, l), this))

Feel free to use and edit my idea or just deny it