[Sync] Gracefully handle writing to a node when the cryptographer is not ready.

chrome/browser/sync/engine/nigori_util.h

 // 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.
 
 // Various utility methods for nigori-based multi-type encryption.
 
 #ifndef CHROME_BROWSER_SYNC_ENGINE_NIGORI_UTIL_H_
 #define CHROME_BROWSER_SYNC_ENGINE_NIGORI_UTIL_H_
 #pragma once
 
 #include "chrome/browser/sync/protocol/nigori_specifics.pb.h"
 #include "chrome/browser/sync/syncable/model_type.h"
 
 namespace browser_sync {
 class Cryptographer;
 }
 
+namespace sync_pb {
+class EntitySpecifics;
+}
+
 namespace syncable {
 
 const char kEncryptedString[] = "encrypted";
 
 class BaseTransaction;
+class Entry;
 class ReadTransaction;
 class WriteTransaction;
 
 // Set the encrypted datatypes on the nigori node.
 void FillNigoriEncryptedTypes(const ModelTypeSet& types,
     sync_pb::NigoriSpecifics* nigori);
 
 // Check if our unsyced changes are encrypted if they need to be based on
 // |encrypted_types|.
 // Returns: true if all unsynced data that should be encrypted is.
 //          false if some unsynced changes need to be encrypted.
 // This method is similar to ProcessUnsyncedChangesForEncryption but does not
 // modify the data and does not care if data is unnecessarily encrypted.
 bool VerifyUnsyncedChangesAreEncrypted(
     BaseTransaction* const trans,
     const ModelTypeSet& encrypted_types);
 
 // Processes all unsynced changes and ensures they are appropriately encrypted
 // or unencrypted, based on |encrypted_types|.
 bool ProcessUnsyncedChangesForEncryption(
     WriteTransaction* const trans,
     browser_sync::Cryptographer* cryptographer);
 
+// Returns true if the entry requires encryption but is not encrypted, false
+// otherwise. Note: this does not check that already encrypted entries are
+// encrypted with the proper key.
+bool EntryNeedsEncryption(const ModelTypeSet& encrypted_types,
+                          const Entry& entry);
+
+// Same as EntryNeedsEncryption, but looks at specifics.
+bool SpecificsNeedsEncryption(const ModelTypeSet& encrypted_types,
+                              const sync_pb::EntitySpecifics& specifics);
+
 // Verifies all data of type |type| is encrypted appropriately.
 bool VerifyDataTypeEncryption(BaseTransaction* const trans,
                               browser_sync::Cryptographer* cryptographer,
                               ModelType type,
                               bool is_encrypted);
 
 }  // namespace syncable
 
 #endif  // CHROME_BROWSER_SYNC_ENGINE_NIGORI_UTIL_H_