SPIGOT-4825: Clearly error on asynchronous tile access

nms-patches/World.patch

@@ -312,7 +312,7 @@
                      }
                  }
              }
-@@ -626,6 +838,7 @@
+@@ -626,14 +838,21 @@
          }
      }
  
@@ -320,9 +320,11 @@
      @Nullable
      @Override
      public TileEntity getTileEntity(BlockPosition blockposition) {
-@@ -634,6 +847,12 @@
+         if (isInsideWorld(blockposition)) {
-         } else if (!this.isClientSide && Thread.currentThread() != this.c) {
              return null;
+         } else if (!this.isClientSide && Thread.currentThread() != this.c) {
+-            return null;
++            throw new IllegalStateException("Asynchronous tile access"); // CraftBukkit - catch
          } else {
 +            // CraftBukkit start
 +            if (capturedTileEntities.containsKey(blockposition)) {