BB importer: address review comment

doc/workflow/importing/import_projects_from_bitbucket.md

@@ -20,7 +20,7 @@ It takes just a few steps to import your existing Bitbucket projects to GitLab.
 
 ![Import projects](bitbucket_importer/bitbucket_import_select_project.png)
 
-A new GitLab project will be created with your imported data. Keep in mind that if you want to Bitbucket users
+A new GitLab project will be created with your imported data. Keep in mind that if you want Bitbucket users
 to be linked to GitLab user you have to have all of them in GitLab in advance. They will be matched by their BitBucket username.
 
 ### Note

lib/gitlab/bitbucket_import/importer.rb

@@ -28,6 +28,7 @@ module Gitlab
 
       def handle_errors
         return unless errors.any?
+
         project.update_column(:import_error, {
           message: 'The remote data could not be fully imported.',
           errors: errors
@@ -35,15 +36,12 @@ module Gitlab
       end
 
       def gitlab_user_id(project, username)
-        if username
-          user = find_user(username)
-          (user && user.id) || project.creator_id
-        else
-          project.creator_id
-        end
+        user = find_user(username)
+        user.try(:id) || project.creator_id
       end
 
       def find_user(username)
+        return nil unless username
         User.joins(:identities).find_by("identities.extern_uid = ? AND identities.provider = 'bitbucket'", username)
       end