Remove MOZ_B2G leftovers and some dead B2G-only components.

dom/indexedDB/IDBObjectStore.cpp

@@ -859,10 +859,6 @@ public:
   }
 };
 
-// We don't need to upgrade database on B2G. See the comment in ActorsParent.cpp,
-// UpgradeSchemaFrom18_0To19_0()
-#if !defined(MOZ_B2G)
-
 class UpgradeDeserializationHelper
 {
 public:
@@ -929,8 +925,6 @@ public:
   }
 };
 
-#endif // MOZ_B2G
-
 template <class Traits>
 JSObject*
 CommonStructuredCloneReadCallback(JSContext* aCx,
@@ -1263,8 +1257,6 @@ IDBObjectStore::DeserializeIndexValue(JSContext* aCx,
   return true;
 }
 
-#if !defined(MOZ_B2G)
-
 // static
 bool
 IDBObjectStore::DeserializeUpgradeValue(JSContext* aCx,
@@ -1301,8 +1293,6 @@ IDBObjectStore::DeserializeUpgradeValue(JSContext* aCx,
   return true;
 }
 
-#endif // MOZ_B2G
-
 #ifdef DEBUG
 
 void