Revert "Extinguish burning creatures in gas-obstructing tiles"

This reverts commit 928f4cf. In playtesting,
the staff of obstruction was highlighted as a means of holding a monster in
place for killing with other staves, including firebolt. As this change was
quite significant for that area of gameplay, I considered it too much for
CE right now so I am reverting it.

CHANGELOG.md

@@ -6,10 +6,6 @@ unreleased
 -
   The frequencies of various special ally-related rooms have been reverted
   to their 1.7.4 values
--
-  Burning creatures are now extinguished when encased in a solid tile,
-  such as crystal from a staff of obstruction. (Does not apply to those
-  which burn unceasingly)
 -
   Wands of plenty now reduce the the maximum health of the target by 50%
   before cloning

src/brogue/Time.c

@@ -188,8 +188,8 @@ void applyInstantTileEffectsToCreature(creature *monst) {
         }
     }
 
-    // Water and "solid" tiles (ones which gas cannot occupy) put out fire.
-    if ((cellHasTMFlag(*x, *y, TM_EXTINGUISHES_FIRE) || cellHasTerrainFlag(*x, *y, T_OBSTRUCTS_GAS))
+    // Water puts out fire.
+    if (cellHasTMFlag(*x, *y, TM_EXTINGUISHES_FIRE)
         && monst->status[STATUS_BURNING]
         && !monst->status[STATUS_LEVITATING]
         && !(monst->info.flags & MONST_ATTACKABLE_THRU_WALLS)