Reduce a duplicate consistency check when applying a new version (#10169)

Summary:
One consistency check in SaveTo() is dupilcated with the one within Apply(). Remove one of then in release mode to reduce time spent in DB mutex.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10169

Test Plan: Run existing tests and see nothing breaks.

Reviewed By: ltamasi

Differential Revision: D37157821

fbshipit-source-id: 73b89443a20b43362ff66d10b9212022034a8234

db/version_builder.cc

@@ -1144,10 +1144,15 @@ class VersionBuilder::Rep {
 
   // Save the current state in *vstorage.
   Status SaveTo(VersionStorageInfo* vstorage) const {
-    Status s = CheckConsistency(base_vstorage_);
+    Status s;
+
+#ifndef NDEBUG
+    // The same check is done within Apply() so we skip it in release mode.
+    s = CheckConsistency(base_vstorage_);
     if (!s.ok()) {
       return s;
     }
+#endif  // NDEBUG
 
     s = CheckConsistency(vstorage);
     if (!s.ok()) {