[Bleeding] Fix exception in getChunkSnapshot() - sky light can be null

src/main/java/org/bukkit/craftbukkit/CraftChunk.java

@@ -193,8 +193,12 @@ public class CraftChunk implements Chunk {
                 /* Get block data nibbles */
                 sectionBlockData[i] = new byte[2048];
                 System.arraycopy(cs[i].j().a, 0, sectionBlockData[i], 0, 2048); // Should be getData
+                if (cs[i].l() == null) {
+                    sectionSkyLights[i] = emptyData;
+                } else {
                     sectionSkyLights[i] = new byte[2048];
                     System.arraycopy(cs[i].l().a, 0, sectionSkyLights[i], 0, 2048); // Should be getSkyLight
+                }
                 sectionEmitLights[i] = new byte[2048];
                 System.arraycopy(cs[i].k().a, 0, sectionEmitLights[i], 0, 2048); // Should be getBlockLight
             }