Grant Okawaru piety (and gifts) for quality not quantity.

This is currently problematic on dungeon levels up to around D:8 as you find
loads of popcorn interspersed with few actual challenges (which in turn are
often enough to kill you), which gives hardly any piety.

I'm forcing this for now to give us an incentive to do something to monster
generation, if it won't be fixed we can disable this for a yet another
release.

Note that contrary to what some think, this formula would make little sense
for most other gods, especially that they already give more piety for higher
HD enemies.  Making it almost exclusive for hardest battles can be explained
for Okawaru, other gods have no theme reasons to reward recklessly running
into danger.  It'd need major balancing, too.

crawl-ref/source/godconduct.cc

@@ -344,9 +344,6 @@ bool did_god_conduct(conduct_type thing_done, int level, bool known,
 
             case GOD_KIKUBAAQUDGHA:
             case GOD_YREDELEMNUL:
-#ifndef NEW_OKAWARU_PIETY
-            case GOD_OKAWARU:
-#endif
             case GOD_VEHUMET:
             case GOD_MAKHLEB:
             case GOD_TROG:
@@ -375,9 +372,6 @@ bool did_god_conduct(conduct_type thing_done, int level, bool known,
             switch (you.religion)
             {
             case GOD_SHINING_ONE:
-#ifndef NEW_OKAWARU_PIETY
-            case GOD_OKAWARU:
-#endif
             case GOD_VEHUMET:
             case GOD_MAKHLEB:
             case GOD_BEOGH:
@@ -404,9 +398,6 @@ bool did_god_conduct(conduct_type thing_done, int level, bool known,
             switch (you.religion)
             {
             case GOD_SHINING_ONE:
-#ifndef NEW_OKAWARU_PIETY
-            case GOD_OKAWARU:
-#endif
             case GOD_MAKHLEB:
             case GOD_TROG:
             case GOD_KIKUBAAQUDGHA:
@@ -541,9 +532,6 @@ bool did_god_conduct(conduct_type thing_done, int level, bool known,
             case GOD_MAKHLEB:
             case GOD_BEOGH:
             case GOD_LUGONU:
-#ifndef NEW_OKAWARU_PIETY
-            case GOD_OKAWARU:
-#endif
                 if (god_hates_attacking_friend(you.religion, victim))
                     break;
 
@@ -1008,7 +996,6 @@ bool did_god_conduct(conduct_type thing_done, int level, bool known,
             break;
         }
 
-#ifdef NEW_OKAWARU_PIETY
         if (you.religion == GOD_OKAWARU
             // currently no constructs and plants
             && (thing_done == DID_KILL_LIVING
@@ -1027,7 +1014,6 @@ bool did_god_conduct(conduct_type thing_done, int level, bool known,
                 simple_god_message(" accepts your kill.");
             retval = true;
         }
-#endif
 
 #ifdef DEBUG_DIAGNOSTICS
         int old_piety = you.piety;

crawl-ref/source/godprayer.cc

@@ -581,7 +581,6 @@ static bool _destroyed_valuable_weapon(int value, int type)
 
 static piety_gain_t _sac_corpse(const item_def& item)
 {
-#ifdef NEW_OKAWARU_PIETY
     if (you.religion == GOD_OKAWARU)
     {
         monster dummy;
@@ -598,7 +597,6 @@ static piety_gain_t _sac_corpse(const item_def& item)
         gain = div_rand_round(gain, 700);
         return (gain <= 0) ? PIETY_NONE : (gain < 4) ? PIETY_SOME : PIETY_LOTS;
     }
-#endif
 
     gain_piety(13, 19);