[Sync] The cryptographer should be able to handle empty or old nigori nodes.

chrome/browser/sync/util/cryptographer.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 <algorithm>
+
 #include "base/base64.h"
 #include "chrome/browser/sync/util/cryptographer.h"
 #include "chrome/browser/password_manager/encryptor.h"
 
 namespace browser_sync {
 
 const char kNigoriTag[] = "google_chrome_nigori";
 
 // We name a particular Nigori instance (ie. a triplet consisting of a hostname,
 // a username, and a password) by calling Permute on this string. Since the
@@ skipping 304 matching lines @@
 
   // Note: the initial version with encryption did not support the
   // encrypt_everything field. If anything more than the sensitive types were
   // encrypted, it meant we were encrypting everything.
   if (!nigori.has_encrypt_everything() &&
       encrypted_types.size() > SensitiveTypes().size()) {
     set_encrypt_everything();
     return;
   }
 
-  SetEncryptedTypes(encrypted_types);
+  MergeEncryptedTypes(encrypted_types);
 }
 
 void Cryptographer::UpdateNigoriFromEncryptedTypes(
     sync_pb::NigoriSpecifics* nigori) const {
   nigori->set_encrypt_everything(encrypt_everything_);
   nigori->set_encrypt_bookmarks(
       encrypted_types_.count(syncable::BOOKMARKS) > 0);
   nigori->set_encrypt_preferences(
       encrypted_types_.count(syncable::PREFERENCES) > 0);
   nigori->set_encrypt_autofill_profile(
@@ skipping 29 matching lines @@
 }
 
 bool Cryptographer::encrypt_everything() const {
   return encrypt_everything_;
 }
 
 syncable::ModelTypeSet Cryptographer::GetEncryptedTypes() const {
   return encrypted_types_;
 }
 
-void Cryptographer::SetEncryptedTypesForTest(
+void Cryptographer::MergeEncryptedTypesForTest(
     const syncable::ModelTypeSet& encrypted_types) {
-  SetEncryptedTypes(encrypted_types);
+  MergeEncryptedTypes(encrypted_types);
 }
 
-void Cryptographer::SetEncryptedTypes(
+void Cryptographer::MergeEncryptedTypes(
     const syncable::ModelTypeSet& encrypted_types) {
-  if (encrypted_types_ == encrypted_types) {
+  if (std::includes(encrypted_types_.begin(), encrypted_types_.end(),
+                    encrypted_types.begin(), encrypted_types.end())) {
     return;
   }
   encrypted_types_.insert(encrypted_types.begin(), encrypted_types.end());
   EmitEncryptedTypesChangedNotification();
 }
 
 void Cryptographer::EmitEncryptedTypesChangedNotification() {
   FOR_EACH_OBSERVER(
       Observer, observers_,
       OnEncryptedTypesChanged(encrypted_types_, encrypt_everything_));
@@ skipping 14 matching lines @@
         continue;
       }
       nigoris_[key.name()] = make_linked_ptr(new_nigori.release());
     }
   }
   DCHECK(nigoris_.end() != nigoris_.find(default_key_name));
   default_nigori_ = &*nigoris_.find(default_key_name);
 }
 
 }  // namespace browser_sync