Scripts/Spells: Implement Holy Mending

Port From (https://github.com/TrinityCore/TrinityCore/commit/277497fdf1ca5f7b310c4544e8f1304a66034884)

Source/Scripts/Spells/Priest.cs

@@ -50,6 +50,7 @@ namespace Scripts.Spells.Priest
         public const uint HaloShadowDamage = 390964;
         public const uint HaloShadowHeal = 390971;
         public const uint Heal = 2060;
+        public const uint HolyMendingHeal = 391156;
         public const uint HolyWordChastise = 88625;
         public const uint HolyWordSanctify = 34861;
         public const uint HolyWordSerenity = 2050;
@@ -558,6 +559,31 @@ namespace Scripts.Spells.Priest
         }
     }
 
+    [Script] // 391154 - Holy Mending
+    class spell_pri_holy_mending : AuraScript
+    {
+        public override bool Validate(SpellInfo spellInfo)
+        {
+            return ValidateSpellInfo(SpellIds.Renew, SpellIds.HolyMendingHeal);
+        }
+
+        bool CheckProc(AuraEffect aurEff, ProcEventInfo procInfo)
+        {
+            return procInfo.GetProcTarget().HasAura(SpellIds.Renew, procInfo.GetActor().GetGUID());
+        }
+
+        void HandleProc(AuraEffect aurEff, ProcEventInfo eventInfo)
+        {
+            eventInfo.GetActor().CastSpell(eventInfo.GetProcTarget(), SpellIds.HolyMendingHeal, new CastSpellExtraArgs(aurEff));
+        }
+
+        public override void Register()
+        {
+            DoCheckEffectProc.Add(new CheckEffectProcHandler(CheckProc, 0, AuraType.ProcTriggerSpell));
+            OnEffectProc.Add(new EffectProcHandler(HandleProc, 0, AuraType.ProcTriggerSpell));
+        }
+    }
+    
     [Script] // 63733 - Holy Words
     class spell_pri_holy_words : AuraScript
     {