Core/Spells: rework part 5: GameObject casting

src/server/game/Spells/SpellScript.cpp

@@ -186,12 +186,17 @@ bool SpellScript::IsInEffectHook() const
 
 Unit* SpellScript::GetCaster() const
 {
-     return m_spell->GetCaster();
+    return m_spell->GetCaster()->ToUnit();
+}
+
+GameObject* SpellScript::GetGObjCaster() const
+{
+    return m_spell->GetCaster()->ToGameObject();
 }
 
 Unit* SpellScript::GetOriginalCaster() const
 {
-     return m_spell->GetOriginalCaster();
+    return m_spell->GetOriginalCaster();
 }
 
 SpellInfo const* SpellScript::GetSpellInfo() const
@@ -642,7 +647,16 @@ ObjectGuid AuraScript::GetCasterGUID() const
 
 Unit* AuraScript::GetCaster() const
 {
-    return m_aura->GetCaster();
+    if (WorldObject* caster = m_aura->GetCaster())
+        return caster->ToUnit();
+    return nullptr;
+}
+
+GameObject* AuraScript::GetGObjCaster() const
+{
+    if (WorldObject* caster = m_aura->GetCaster())
+        return caster->ToGameObject();
+    return nullptr;
 }
 
 WorldObject* AuraScript::GetOwner() const