Add Player#sendHealthUpdate (#6904)

patches/api/Add-player-health-update-API.patch

@@ -0,0 +1,42 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: SamB440 <sam@islandearth.net>
+Date: Wed, 17 Nov 2021 12:30:36 +0000
+Subject: [PATCH] Add player health update API
+
+
+diff --git a/src/main/java/org/bukkit/entity/Player.java b/src/main/java/org/bukkit/entity/Player.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/org/bukkit/entity/Player.java
++++ b/src/main/java/org/bukkit/entity/Player.java
+@@ -0,0 +0,0 @@ public interface Player extends HumanEntity, Conversable, OfflinePlayer, PluginM
+      */
+     public double getHealthScale();
+ 
++    // Paper start
++    /**
++     * Forcefully sends a health update to the player.
++     * <p>This method can cause the client to display health values
++     * different to their true server values. If the player takes damage or
++     * causes an action to otherwise cause a health update, these values
++     * will no longer be shown.</p>
++     * Setting the visible health to 0 will result in the client seeing
++     * the death screen, unable to press the respawn button.
++     * @see #sendHealthUpdate()
++     * @param health the health of the player
++     * @param foodLevel the food level of the player
++     * @param saturationLevel the saturation level of the player
++     */
++    public void sendHealthUpdate(final double health, final int foodLevel, final float saturationLevel);
++    
++    /**
++     * Forcefully sends a health update to the player.
++     * This uses the player's current health, saturation, and food level.
++     * <p>Use after {@link #setHealth(double)} to show the heart animation
++     * of gaining or losing health.</p>
++     */
++    public void sendHealthUpdate();
++    // Paper end
++    
+     /**
+      * Gets the entity which is followed by the camera when in
+      * {@link GameMode#SPECTATOR}.

patches/server/Add-player-health-update-API.patch

@@ -0,0 +1,39 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: SamB440 <sam@islandearth.net>
+Date: Wed, 17 Nov 2021 12:31:42 +0000
+Subject: [PATCH] Add player health update API
+
+
+diff --git a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+index 0000000000000000000000000000000000000000..0000000000000000000000000000000000000000 100644
+--- a/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
++++ b/src/main/java/org/bukkit/craftbukkit/entity/CraftPlayer.java
+@@ -0,0 +0,0 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
+         this.getHandle().maxHealthCache = getMaxHealth();
+     }
+ 
+-    public void sendHealthUpdate() {
++    // Paper start
++    @Override
++    public void sendHealthUpdate(final double health, final int foodLevel, final float saturationLevel) {
+         // Paper start - cancellable death event
+-        ClientboundSetHealthPacket packet = new ClientboundSetHealthPacket(this.getScaledHealth(), this.getHandle().getFoodData().getFoodLevel(), this.getHandle().getFoodData().getSaturationLevel());
++        ClientboundSetHealthPacket packet = new ClientboundSetHealthPacket((float) health, foodLevel, saturationLevel);
+         if (this.getHandle().queueHealthUpdatePacket) {
+             this.getHandle().queuedHealthUpdatePacket = packet;
+         } else {
+@@ -0,0 +0,0 @@ public class CraftPlayer extends CraftHumanEntity implements Player {
+         }
+         // Paper end
+     }
+-
++    
++    @Override
++    public void sendHealthUpdate() {
++        this.sendHealthUpdate(this.getScaledHealth(), this.getHandle().getFoodData().getFoodLevel(), this.getHandle().getFoodData().getSaturationLevel());
++    }
++    // Paper end
++    
+     public void injectScaledMaxHealth(Collection<AttributeInstance> collection, boolean force) {
+         if (!this.scaledHealth && !force) {
+             return;