Undo PokeCodec's PRs

This commit undoes most of PokeCodec's PRs after the debate in chat. Some
harmless or completely superseded PRs have been left alone, as there is not
much benefit in attempting to undo them.

Reverts #1104, #1108, #1115, #1118, #1119, #1124, #1126, #1127, #1132, #1136,
#1137, #1139, #1140, #1144, #1148, #1149, #1150, #1153, #1155, #1177, #1179,
#1180, #1181, #1182 and #1183.

src/battle_tower.c

@@ -1447,7 +1447,7 @@ u8 GetFrontierOpponentClass(u16 trainerId)
     }
     else if (trainerId == TRAINER_FRONTIER_BRAIN)
     {
-        return GetFrontierBrainTrainerClass(); // This sticks out like a sore thumb, but this is the only other way that matches. Maybe it SHOULD be assigned to ret, or all early returns. I don't know.
+        trainerClass = GetFrontierBrainTrainerClass();
     }
     else if (trainerId == TRAINER_STEVEN_PARTNER)
     {
@@ -1466,6 +1466,9 @@ u8 GetFrontierOpponentClass(u16 trainerId)
         else
         {
             trainerClass = gFacilityClassToTrainerClass[gSaveBlock2Ptr->frontier.towerRecords[trainerId - TRAINER_RECORD_MIXING_FRIEND].facilityClass];
+            #ifndef NONMATCHING
+                asm("");
+            #endif
         }
     }
     else
@@ -1477,6 +1480,9 @@ u8 GetFrontierOpponentClass(u16 trainerId)
         else
         {
             trainerClass = gFacilityClassToTrainerClass[gApprentices[gSaveBlock2Ptr->apprentices[trainerId - TRAINER_RECORD_MIXING_APPRENTICE].id].facilityClass];
+            #ifndef NONMATCHING
+                asm("");
+            #endif
         }
     }