Remove Water optimization from the Light Optimizations

case was found where it could cause light to become incorrect

But we still get to optimize out any same block updates which reduces light operations

Spigot-Server-Patches/Optimize-Light-Recalculations.patch

@@ -10,38 +10,21 @@ do not impact light calculations.
 So the only way light should change, is if the block itself
 changes from 1 block to another.
 
-Additionally, as of 1.13, water now only blocks 1 light level
-instead of 3, meaning that light level decreasing is the same as air.
-
-This means, transitions between water and air also do not need
-to recalculate light, which saves a TON of updates caused by
-fluids flowing.
-
 diff --git a/src/main/java/net/minecraft/server/Chunk.java b/src/main/java/net/minecraft/server/Chunk.java
-index 53aab97866..dad294ecbe 100644
+index 53aab97866..e4bda70bb9 100644
 --- a/src/main/java/net/minecraft/server/Chunk.java
 +++ b/src/main/java/net/minecraft/server/Chunk.java
-@@ -0,0 +0,0 @@ public class Chunk implements IChunkAccess {
-     // Keep this synced with entitySlices.add() and entitySlices.remove()
-     private final int[] itemCounts = new int[16];
-     private final int[] inventoryEntityCounts = new int[16];
-+    public static boolean shouldRecheckLight(Block block, Block block1) {
-+        return !(block == block1 || (block1 == Blocks.WATER && block == Blocks.AIR) || (block == Blocks.WATER && block1 == Blocks.AIR));
-+    }
-     // Paper end
-     public boolean areNeighborsLoaded(final int radius) {
-         switch (radius) {
 @@ -0,0 +0,0 @@ public class Chunk implements IChunkAccess {
              } else {
                  if (flag1) {
                      this.initLighting();
 -                } else {
-+                } else if (shouldRecheckLight(block, block1)) { // Paper - Optimize light recalculations
++                } else if (block != block1) { // Paper - Optimize light recalculations
                      this.runOrQueueLightUpdate(() -> { // Paper - Queue light update
                      int i1 = iblockdata.b(this.world, blockposition);
                      int j1 = iblockdata1.b(this.world, blockposition);
 diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
-index 13f69f1b82..cd25bf3d9e 100644
+index 13f69f1b82..763401835d 100644
 --- a/src/main/java/net/minecraft/server/World.java
 +++ b/src/main/java/net/minecraft/server/World.java
 @@ -0,0 +0,0 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
@@ -49,7 +32,7 @@ index 13f69f1b82..cd25bf3d9e 100644
                  IBlockData iblockdata2 = this.getType(blockposition);
  
 -                if (iblockdata2.b(this, blockposition) != iblockdata1.b(this, blockposition) || iblockdata2.e() != iblockdata1.e()) {
-+                if (Chunk.shouldRecheckLight(iblockdata.getBlock(), iblockdata2.getBlock()) && iblockdata2.b(this, blockposition) != iblockdata1.b(this, blockposition) || iblockdata2.e() != iblockdata1.e()) { // Paper - optimize light recalculations
++                if (iblockdata.getBlock() != iblockdata2.getBlock() && iblockdata2.b(this, blockposition) != iblockdata1.b(this, blockposition) || iblockdata2.e() != iblockdata1.e()) { // Paper - optimize light recalculations
                      this.methodProfiler.a("checkLight");
                      chunk.runOrQueueLightUpdate(() -> this.r(blockposition)); // Paper - Queue light update
                      this.methodProfiler.e();