message: Added score_threshold parameter to control the precions/recall trade-off.
  We will find the optimal threshold with offline evaluations and verify
  them in LE.
diff: @@ -849,6 +849,10 @@ message ApplicationInfo {
  message CheckSpellingRequest {
  // spellchecker request.
  optional string text = 1;
  + // Run spelling correction if
  + // score(suggestion) - score(original) >= score_threshold.
  + // Used to control the precision/recall trade-off.
  + optional float score_threshold = 2;
  }
  // Spellchecker response.
  