[Sync] Make GetFirstChildId return a flag indicating success

chrome/browser/sync/engine/nigori_util.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/sync/engine/nigori_util.h"
 
 #include <queue>
 #include <string>
 #include <vector>
 
@@ skipping 63 matching lines @@
                               const sync_pb::EntitySpecifics& specifics) {
   ModelType type = GetModelTypeFromSpecifics(specifics);
   if (type == PASSWORDS || type == NIGORI)
     return false;  // These types have their own encryption schemes.
   if (encrypted_types.count(type) == 0)
     return false;  // This type does not require encryption
   return !specifics.has_encrypted();
 }
 
 // Mainly for testing.
-bool VerifyDataTypeEncryption(BaseTransaction* const trans,
-                              browser_sync::Cryptographer* cryptographer,
-                              ModelType type,
-                              bool is_encrypted) {
+bool VerifyDataTypeEncryptionForTest(
+    BaseTransaction* const trans,
+    browser_sync::Cryptographer* cryptographer,
+    ModelType type,
+    bool is_encrypted) {
   if (type == PASSWORDS || type == NIGORI) {
     NOTREACHED();
     return true;
   }
   std::string type_tag = ModelTypeToRootTag(type);
   Entry type_root(trans, GET_BY_SERVER_TAG, type_tag);
   if (!type_root.good()) {
     NOTREACHED();
     return false;
   }
 
   std::queue<Id> to_visit;
-  Id id_string =
-      trans->directory()->GetFirstChildId(trans, type_root.Get(ID));
+  Id id_string;
+  if (!trans->directory()->GetFirstChildId(
+          trans, type_root.Get(ID), &id_string)) {
+    NOTREACHED();
+    return false;
+  }
   to_visit.push(id_string);
   while (!to_visit.empty()) {
     id_string = to_visit.front();
     to_visit.pop();
     if (id_string.IsRoot())
       continue;
 
     Entry child(trans, GET_BY_ID, id_string);
     if (!child.good()) {
       NOTREACHED();
       return false;
     }
     if (child.Get(IS_DIR)) {
+      Id child_id_string;
+      if (!trans->directory()->GetFirstChildId(
+              trans, child.Get(ID), &child_id_string)) {
+        NOTREACHED();
+        return false;
+      }
       // Traverse the children.
-      to_visit.push(
-          trans->directory()->GetFirstChildId(trans, child.Get(ID)));
+      to_visit.push(child_id_string);
     }
     const sync_pb::EntitySpecifics& specifics = child.Get(SPECIFICS);
     DCHECK_EQ(type, child.GetModelType());
     DCHECK_EQ(type, GetModelTypeFromSpecifics(specifics));
     // We don't encrypt the server's permanent items.
     if (child.Get(UNIQUE_SERVER_TAG).empty()) {
       if (specifics.has_encrypted() != is_encrypted)
         return false;
       if (specifics.has_encrypted()) {
         if (child.Get(NON_UNIQUE_NAME) != kEncryptedString)
           return false;
         if (!cryptographer->CanDecryptUsingDefaultKey(specifics.encrypted()))
           return false;
       }
     }
     // Push the successor.
     to_visit.push(child.Get(NEXT_ID));
   }
   return true;
 }
 
 }  // namespace syncable