Fix Stackable ShulkerBoxes (#329)

patches/server/0040-Stackable-ShulkerBoxes.patch

@@ -134,7 +134,7 @@ index 607f1a9802eb0ff4865af4c53f302128a6e6fe02..929a9bee808e8216dacb74dc58dbeee6
          ItemStack itemstack1 = other.getItem();
 
 diff --git a/src/main/java/net/minecraft/world/entity/player/Inventory.java b/src/main/java/net/minecraft/world/entity/player/Inventory.java
-index eb11482f48c9f330b7fa62a278fd6f07d3a642e1..8631f3a5ce5aa24f195d5031dad6d289e4389314 100644
+index eb11482f48c9f330b7fa62a278fd6f07d3a642e1..62b4aeabbde9561cd7e78fe14b751bd377ba129a 100644
 --- a/src/main/java/net/minecraft/world/entity/player/Inventory.java
 +++ b/src/main/java/net/minecraft/world/entity/player/Inventory.java
 @@ -111,7 +111,7 @@ public class Inventory implements Container, Nameable {
@@ -146,6 +146,22 @@ index eb11482f48c9f330b7fa62a278fd6f07d3a642e1..8631f3a5ce5aa24f195d5031dad6d289
      }
 
      // CraftBukkit start - Watch method above! :D
+@@ -122,13 +122,13 @@ public class Inventory implements Container, Nameable {
+             if (itemstack1.isEmpty()) return itemstack.getCount();
+
+             if (this.hasRemainingSpaceForItem(itemstack1, itemstack)) {
+-                remains -= (itemstack1.getMaxStackSize() < this.getMaxStackSize() ? itemstack1.getMaxStackSize() : this.getMaxStackSize()) - itemstack1.getCount();
++                remains -= (org.leavesmc.leaves.util.ShulkerBoxUtils.getItemStackMaxCount(itemstack1) < this.getMaxStackSize() ? org.leavesmc.leaves.util.ShulkerBoxUtils.getItemStackMaxCount(itemstack1) : this.getMaxStackSize()) - itemstack1.getCount(); // Leaves
+             }
+             if (remains <= 0) return itemstack.getCount();
+         }
+         ItemStack offhandItemStack = this.getItem(this.items.size() + this.armor.size());
+         if (this.hasRemainingSpaceForItem(offhandItemStack, itemstack)) {
+-            remains -= (offhandItemStack.getMaxStackSize() < this.getMaxStackSize() ? offhandItemStack.getMaxStackSize() : this.getMaxStackSize()) - offhandItemStack.getCount();
++            remains -= (org.leavesmc.leaves.util.ShulkerBoxUtils.getItemStackMaxCount(offhandItemStack) < this.getMaxStackSize() ? org.leavesmc.leaves.util.ShulkerBoxUtils.getItemStackMaxCount(offhandItemStack) : this.getMaxStackSize()) - offhandItemStack.getCount(); // Leaves
+         }
+         if (remains <= 0) return itemstack.getCount();
+
 @@ -279,7 +279,9 @@ public class Inventory implements Container, Nameable {
              this.setItem(slot, itemstack1);
          }