Fix Buildings::setOwner() persistence

Needed to set bld->owner_id for changes to persist across save/load

Fixes #983, thanks to Quietust

NEWS.rst

@@ -41,6 +41,10 @@ New Scripts
 -----------
 - `load-save`: loads a save non-interactively
 
+Fixes
+-----
+- Buildings::setOwner() changes now persist properly when saved
+
 DFHack 0.43.03-r1
 =================
 

library/modules/Buildings.cpp

@@ -239,6 +239,7 @@ bool Buildings::setOwner(df::building *bld, df::unit *unit)
 
     if (unit)
     {
+        bld->owner_id = unit->id;
         unit->owned_buildings.push_back(bld);
 
         if (auto spouse = df::unit::find(unit->relationship_ids[df::unit_relationship_type::Spouse]))
@@ -248,6 +249,10 @@ bool Buildings::setOwner(df::building *bld, df::unit *unit)
                 blist.push_back(bld);
         }
     }
+    else
+    {
+        bld->owner_id = -1;
+    }
 
     return true;
 }