Made grass throw a BlockSpread event when growing and a BlockFade event when receding.

src/main/java/net/minecraft/server/BlockGrass.java

@@ -0,0 +1,67 @@
+package net.minecraft.server;
+
+import java.util.Random;
+
+// CraftBukkit start
+import org.bukkit.event.block.BlockSpreadEvent;
+import org.bukkit.event.block.BlockFadeEvent;
+//CraftBukkit end
+
+public class BlockGrass extends Block {
+
+    protected BlockGrass(int i) {
+        super(i, Material.GRASS);
+        this.textureId = 3;
+        this.a(true);
+    }
+
+    public int a(int i, int j) {
+        return i == 1 ? 0 : (i == 0 ? 2 : 3);
+    }
+
+    public void a(World world, int i, int j, int k, Random random) {
+        if (!world.isStatic) {
+            if (world.getLightLevel(i, j + 1, k) < 4 && Block.q[world.getTypeId(i, j + 1, k)] > 2) {
+                if (random.nextInt(4) != 0) {
+                    return;
+                }
+                // CraftBukkit start
+                org.bukkit.World bworld = world.getWorld();
+                org.bukkit.block.BlockState blockState = bworld.getBlockAt(i, j, k).getState();
+                blockState.setTypeId(Block.DIRT.id);
+
+                BlockFadeEvent event = new BlockFadeEvent(blockState.getBlock(), blockState);
+                world.getServer().getPluginManager().callEvent(event);
+
+                if (!event.isCancelled()) {
+                    blockState.update(true);
+                }
+                // CraftBukkit end
+            } else if (world.getLightLevel(i, j + 1, k) >= 9) {
+                int l = i + random.nextInt(3) - 1;
+                int i1 = j + random.nextInt(5) - 3;
+                int j1 = k + random.nextInt(3) - 1;
+                int k1 = world.getTypeId(l, i1 + 1, j1);
+
+                if (world.getTypeId(l, i1, j1) == Block.DIRT.id && world.getLightLevel(l, i1 + 1, j1) >= 4 && Block.q[k1] <= 2) {
+                    // CraftBukkit start
+                    org.bukkit.World bworld = world.getWorld();
+                    org.bukkit.block.BlockState blockState = bworld.getBlockAt(l, i1, j1).getState();
+                    blockState.setTypeId(this.id);
+
+                    BlockSpreadEvent event = new BlockSpreadEvent(blockState.getBlock(), bworld.getBlockAt(i, j, k), blockState);
+                    world.getServer().getPluginManager().callEvent(event);
+
+                    if (!event.isCancelled()) {
+                        blockState.update(true);
+                    }
+                    // CraftBukkit end
+                }
+            }
+        }
+    }
+
+    public int a(int i, Random random) {
+        return Block.DIRT.a(0, random);
+    }
+}