Revert a change made to getChunkFuture for isUnloading

Talked with leaf on it and understand what its going now even though
it was a hack fix by Spigot, but seems ok.

I had orig made this change thinking it was the source of another
issue but that came out to not be true.

Fixes #3573

Spigot-Server-Patches/0528-Implement-Chunk-Priority-Urgency-System-for-Chunks.patch

@@ -413,7 +413,7 @@ index 7702fbefa598bce7e6a2d287f7ec36b78a62bff8..f7be94e801e58a39e0efcc813d95bbd6
          public void a() {
              super.a();
 diff --git a/src/main/java/net/minecraft/server/ChunkProviderServer.java b/src/main/java/net/minecraft/server/ChunkProviderServer.java
-index 7a275bf3260f9fbefc41883c5ebdc1eb2196daf0..81a200ea4c533744890b6e19dd0d83f57351906c 100644
+index 7a275bf3260f9fbefc41883c5ebdc1eb2196daf0..b6a7e475c6ebe499c641db5967adb1674323a517 100644
 --- a/src/main/java/net/minecraft/server/ChunkProviderServer.java
 +++ b/src/main/java/net/minecraft/server/ChunkProviderServer.java
 @@ -432,6 +432,26 @@ public class ChunkProviderServer extends IChunkProvider {
@@ -461,12 +461,8 @@ index 7a275bf3260f9fbefc41883c5ebdc1eb2196daf0..81a200ea4c533744890b6e19dd0d83f5
              } // Paper
              ichunkaccess = (IChunkAccess) ((Either) completablefuture.join()).map((ichunkaccess1) -> {
                  return ichunkaccess1;
-@@ -527,13 +551,15 @@ public class ChunkProviderServer extends IChunkProvider {
-             PlayerChunk.State currentChunkState = PlayerChunk.getChunkState(playerchunk.getTicketLevel());
-             currentlyUnloading = (oldChunkState.isAtLeast(PlayerChunk.State.BORDER) && !currentChunkState.isAtLeast(PlayerChunk.State.BORDER));
-         }
--        if (flag && !currentlyUnloading) {
-+        if (flag) { // Paper - don't care about unloading state
+@@ -530,10 +554,12 @@ public class ChunkProviderServer extends IChunkProvider {
+         if (flag && !currentlyUnloading) {
              // CraftBukkit end
              this.chunkMapDistance.a(TicketType.UNKNOWN, chunkcoordintpair, l, chunkcoordintpair);
 +            if (isUrgent) this.chunkMapDistance.markUrgent(chunkcoordintpair); // Paper
@@ -478,7 +474,7 @@ index 7a275bf3260f9fbefc41883c5ebdc1eb2196daf0..81a200ea4c533744890b6e19dd0d83f5
                  this.tickDistanceManager();
                  playerchunk = this.getChunk(k);
                  gameprofilerfiller.exit();
-@@ -542,12 +568,17 @@ public class ChunkProviderServer extends IChunkProvider {
+@@ -542,8 +568,13 @@ public class ChunkProviderServer extends IChunkProvider {
                  }
              }
          }
@@ -494,11 +490,6 @@ index 7a275bf3260f9fbefc41883c5ebdc1eb2196daf0..81a200ea4c533744890b6e19dd0d83f5
      }
  
      private boolean a(@Nullable PlayerChunk playerchunk, int i) {
--        return playerchunk == null || playerchunk.oldTicketLevel > i; // CraftBukkit using oldTicketLevel for isLoaded checks
-+        return playerchunk == null || playerchunk.getTicketLevel() > i; // CraftBukkit using oldTicketLevel for isLoaded checks - Paper - keep vanilla check
-     }
- 
-     public boolean isLoaded(int i, int j) {
 @@ -593,7 +624,8 @@ public class ChunkProviderServer extends IChunkProvider {
          return this.serverThreadQueue.executeNext();
      }