fix g.cubes eating green slime

Back when dead green slime left a corpse, gelatinous cubes wouldn't
eat that, but they would eat globs of green slime without being
affected.  Add the missing glob check so g.cubes will engulf globs
of green slime instead of eating those.

doc/fixes36.1

@@ -367,6 +367,7 @@ when sitting at a trap spot: You sit down. You step on a level teleporter.
 show all statusline information in #attributes
 add option status_updates to prevent bottom of screen status line updates
 fix achievement recording bug with mines and sokoban prizes
+g.cubes would eat globs of green slime without harm; engulf those instead
 
 
 Fixes to Post-3.6.0 Problems that Were Exposed Via git Repository

src/mon.c

@@ -929,7 +929,8 @@ struct monst *mtmp;
                        || otmp->otyp == RIN_SLOW_DIGESTION)
                    /* cockatrice corpses handled above; this
                       touch_petrifies() check catches eggs */
-                   || ((otmp->otyp == CORPSE || otmp->otyp == EGG)
+                   || ((otmp->otyp == CORPSE || otmp->otyp == EGG
+                        || otmp->globby)
                        && ((touch_petrifies(&mons[otmp->corpsenm])
                             && !resists_ston(mtmp))
                            || (otmp->corpsenm == PM_GREEN_SLIME