Avoid leaking Index.aiRowEst memory if an OOM causes a rollback which deletes

the index before the aiRowEst deletion code in sqlite3AnalysisLoad() routine
has a chance to run.  Since the aiRowEst now might be deleted from freeIndex()
which does not always have a db pointer, make sure the aiRowEst memory is
not held in lookaside.

FossilOrigin-Name: efd87ba142723ba131fcc985db6eb45c5a3c637b

src/build.c

@@ -435,6 +435,9 @@ static void freeIndex(sqlite3 *db, Index *p){
   sqlite3ExprDelete(db, p->pPartIdxWhere);
   sqlite3DbFree(db, p->zColAff);
   if( p->isResized ) sqlite3DbFree(db, p->azColl);
+#ifdef SQLITE_ENABLE_STAT3_OR_STAT4
+  sqlite3_free(p->aiRowEst);
+#endif
   sqlite3DbFree(db, p);
 }