Revert of PaymentHandler: Implement PaymentInstruments.keys().

content/browser/service_worker/service_worker_database.cc

Index: content/browser/service_worker/service_worker_database.cc
diff --git a/content/browser/service_worker/service_worker_database.cc b/content/browser/service_worker/service_worker_database.cc
index 535b6a402700aefe223ee0b4d021fdfb54e32c03..2db301c1b627bb2ed9fec1f69b4852c9573194dd 100644
--- a/content/browser/service_worker/service_worker_database.cc
+++ b/content/browser/service_worker/service_worker_database.cc
@@ -881,50 +881,6 @@
   return status;
 }
 
-ServiceWorkerDatabase::Status ServiceWorkerDatabase::ReadUserDataByKeyPrefix(
-    int64_t registration_id,
-    const std::string key_prefix,
-    std::vector<std::string>* user_data_values) {
-  DCHECK(sequence_checker_.CalledOnValidSequence());
-  DCHECK_NE(kInvalidServiceWorkerRegistrationId, registration_id);
-  DCHECK(user_data_values);
-
-  Status status = LazyOpen(false);
-  if (IsNewOrNonexistentDatabase(status))
-    return STATUS_ERROR_NOT_FOUND;
-  if (status != STATUS_OK)
-    return status;
-
-  std::string prefix = CreateUserDataKey(registration_id, key_prefix);
-  {
-    std::unique_ptr<leveldb::Iterator> itr(
-        db_->NewIterator(leveldb::ReadOptions()));
-    for (itr->Seek(prefix); itr->Valid(); itr->Next()) {
-      status = LevelDBStatusToStatus(itr->status());
-      if (status != STATUS_OK) {
-        user_data_values->clear();
-        break;
-      }
-
-      if (!itr->key().starts_with(prefix))
-        break;
-
-      std::string user_data_value;
-      status = LevelDBStatusToStatus(
-          db_->Get(leveldb::ReadOptions(), itr->key(), &user_data_value));
-      if (status != STATUS_OK) {
-        user_data_values->clear();
-        break;
-      }
-
-      user_data_values->push_back(user_data_value);
-    }
-  }
-
-  HandleReadResult(FROM_HERE, status);
-  return status;
-}
-
 ServiceWorkerDatabase::Status ServiceWorkerDatabase::WriteUserData(
     int64_t registration_id,
     const GURL& origin,