Implemented block break XP drops

src/pocketmine/block/Block.php

@@ -471,6 +471,30 @@ class Block extends Position implements BlockIds, Metadatable{
 		];
 	}
 
+	/**
+	 * Returns how much XP will be dropped by breaking this block with the given item.
+	 *
+	 * @param Item $item
+	 *
+	 * @return int
+	 */
+	public function getXpDropForTool(Item $item) : int{
+		if($item->hasEnchantment(Enchantment::SILK_TOUCH) or !$this->isCompatibleWithTool($item)){
+			return 0;
+		}
+
+		return $this->getXpDropAmount();
+	}
+
+	/**
+	 * Returns how much XP this block will drop when broken with an appropriate tool.
+	 *
+	 * @return int
+	 */
+	protected function getXpDropAmount() : int{
+		return 0;
+	}
+
 	/**
 	 * Returns whether Silk Touch enchanted tools will cause this block to drop as itself. Since most blocks drop
 	 * themselves anyway, this is implicitly true.

src/pocketmine/block/CoalOre.php

@@ -57,4 +57,7 @@ class CoalOre extends Solid{
 		];
 	}
 
+	public function getXpDropForTool(Item $item) : int{
+		return mt_rand(0, 2);
+	}
 }

src/pocketmine/block/DiamondOre.php

@@ -56,4 +56,8 @@ class DiamondOre extends Solid{
 			ItemFactory::get(Item::DIAMOND)
 		];
 	}
+
+	protected function getXpDropAmount() : int{
+		return mt_rand(3, 7);
+	}
 }

src/pocketmine/block/LapisOre.php

@@ -57,4 +57,7 @@ class LapisOre extends Solid{
 		];
 	}
 
+	protected function getXpDropAmount() : int{
+		return mt_rand(2, 5);
+	}
 }

src/pocketmine/block/MonsterSpawner.php

@@ -57,4 +57,8 @@ class MonsterSpawner extends Transparent{
 	public function isAffectedBySilkTouch() : bool{
 		return false;
 	}
+
+	protected function getXpDropAmount() : int{
+		return mt_rand(15, 43);
+	}
 }

src/pocketmine/block/NetherQuartzOre.php

@@ -57,4 +57,7 @@ class NetherQuartzOre extends Solid{
 		];
 	}
 
+	protected function getXpDropAmount() : int{
+		return mt_rand(2, 5);
+	}
 }

src/pocketmine/block/RedstoneOre.php

@@ -70,4 +70,8 @@ class RedstoneOre extends Solid{
 			ItemFactory::get(Item::REDSTONE_DUST, 0, mt_rand(4, 5))
 		];
 	}
+
+	protected function getXpDropAmount() : int{
+		return mt_rand(1, 5);
+	}
 }