lava_effects() bit

lava_effects() item destrunction had the logic for handling Book of
the Dead wrong.  (However, that didn't matter since the obj_resists()
check earlier would prevent it from being burned up.  Fix it anyway.)

src/steal.c

@@ -236,9 +236,9 @@ remove_worn_item(
     /*
      * Losing worn gear might drop hero into water or lava or onto a
      * location-changing trap or take away the ability to breathe in water.
-     * Marking it 'in_use' prevents emergency_disrobe() from dropping it.
-     * in_lava() appears to be ok; other cases impacting object location
-     * (or destruction) might still have issues.
+     * Marking it 'in_use' prevents emergency_disrobe() from dropping it
+     * and lava_effects() from destroying it; other cases impacting object
+     * location (or destruction) might still have issues.
      *
      * Note:  if a hangup save occurs when 'in_use' is set, the item will
      * be destroyed via useup() during restore.  Maybe remove_worn_item()

src/trap.c

@@ -6609,11 +6609,11 @@ lava_effects(void)
 
         for (obj = gi.invent; obj; obj = obj2) {
             obj2 = obj->nobj;
-            /* above, we set in_use for objects which are to be destroyed */
             if (obj->o_id == protect_oid) {
-                ; /* skip protected item; caller expects to retain access */
-            } else if (obj->otyp == SPE_BOOK_OF_THE_DEAD && !Blind) {
-                if (usurvive)
+                /* skip protected item; caller expects to retain access */
+                obj->in_use = 1; /* was cleared when setting protect_oid */
+            } else if (obj->otyp == SPE_BOOK_OF_THE_DEAD) {
+                if (usurvive && !Blind)
                     pline("%s glows a strange %s, but remains intact.",
                           The(xname(obj)), hcolor("dark red"));
             } else if (obj->in_use) {