[Sync] Fix encryption/passphrase handling.

chrome/browser/sync/profile_sync_service.h

Index: chrome/browser/sync/profile_sync_service.h
diff --git a/chrome/browser/sync/profile_sync_service.h b/chrome/browser/sync/profile_sync_service.h
index cef7d6185025d8c6c84b7868bacfea5f25ec6cad..0edc4a81e1bdadfae4bbd7024b1e34daf88e693d 100644
--- a/chrome/browser/sync/profile_sync_service.h
+++ b/chrome/browser/sync/profile_sync_service.h
@@ -631,9 +631,8 @@ class ProfileSyncService : public browser_sync::SyncFrontend,
   base::OneShotTimer<ProfileSyncService> clear_server_data_timer_;
 
   // The most recently requested set of types to encrypt. Set by the user,
-  // and cached if the syncer was unable to encrypt new types (for example
-  // because we haven't finished initializing). Cleared when we successfully
-  // post a new encrypt task to the sync backend.
+  // and cached until the syncer either finishes encryption
+  // (OnEncryptionComplete) or the user cancels.
   syncable::ModelTypeSet pending_types_for_encryption_;
 
   scoped_ptr<browser_sync::BackendMigrator> migrator_;