Minor fixes and cleanup

src/lightmap.cpp

@@ -63,7 +63,7 @@ std::string four_quadrants::to_string() const
 }
 
 void map::add_light_from_items( const tripoint &p, item_stack::iterator begin,
-                                map_stack::iterator end )
+                                item_stack::iterator end )
 {
     for( auto itm_it = begin; itm_it != end; ++itm_it ) {
         float ilum = 0.0; // brightness

src/map.cpp

@@ -4132,7 +4132,10 @@ map_stack::iterator map::i_rem( const tripoint &p, map_stack::const_iterator it
 void map::i_rem( const tripoint &p, item *it )
 {
     map_stack map_items = i_at( p );
-    map_items.erase( map_items.get_iterator_from_pointer( it ) );
+    map_stack::const_iterator iter = map_items.get_iterator_from_pointer( it );
+    if( iter != map_items.end() ) {
+        i_rem( p, iter );
+    }
 }
 
 void map::i_clear( const tripoint &p )

src/map.h

@@ -1567,7 +1567,7 @@ class map
         void apply_light_arc( const tripoint &p, int angle, float luminance, int wideangle = 30 );
         void apply_light_ray( bool lit[MAPSIZE_X][MAPSIZE_Y],
                               const tripoint &s, const tripoint &e, float luminance );
-        void add_light_from_items( const tripoint &p, item_stack::iterator begin, map_stack::iterator end );
+        void add_light_from_items( const tripoint &p, item_stack::iterator begin, item_stack::iterator end );
         std::unique_ptr<vehicle> add_vehicle_to_map( std::unique_ptr<vehicle> veh, bool merge_wrecks );
 
         // Internal methods used to bash just the selected features

src/savegame_json.cpp

@@ -3484,7 +3484,7 @@ void submap::load( JsonIn &jsin, const std::string &member_name, bool rubpow_upd
                     return VisitResponse::NEXT;
                 } );
 
-                colony<item>::iterator it = itm[p.x][p.y].insert( tmp );
+                const colony<item>::iterator it = itm[p.x][p.y].insert( tmp );
                 if( tmp.needs_processing() ) {
                     active_items.add( it, p );
                 }

src/vehicle.cpp

@@ -4443,20 +4443,15 @@ cata::optional<vehicle_stack::iterator> vehicle::add_item( int part, const item
     return cata::optional<vehicle_stack::iterator>( new_pos );
 }
 
-bool vehicle::remove_item( int part, const item *it )
+bool vehicle::remove_item( int part, item *it )
 {
-    bool rc = false;
-    colony<item> &veh_items = parts[part].items;
-
-    for( auto iter = veh_items.begin(); iter != veh_items.end(); ++iter ) {
-        //delete the item if the pointer memory addresses are the same
-        if( it == &*iter ) {
-            remove_item( part, iter );
-            rc = true;
-            break;
-        }
+    const colony<item> &veh_items = parts[part].items;
+    const colony<item>::const_iterator iter = veh_items.get_iterator_from_pointer( it );
+    if( iter == veh_items.end() ) {
+        return false
     }
-    return rc;
+    remove_item( part, iter );
+    return true;
 }
 
 vehicle_stack::iterator vehicle::remove_item( int part, vehicle_stack::const_iterator it )