fix some issues with credentials

app/models/project_import_data.rb

@@ -22,7 +22,7 @@ class ProjectImportData < ActiveRecord::Base
   before_validation :symbolize_credentials
 
   def symbolize_credentials
-    return if credentials.blank?
-    credentials.deep_symbolize_keys!
+    # bang doesn't work here
+    self.credentials = self.credentials.deep_symbolize_keys unless self.credentials.blank?
   end
 end

lib/gitlab/bitbucket_import/client.rb

@@ -6,10 +6,10 @@ module Gitlab
       attr_reader :consumer, :api
 
       def self.from_project(project)
-        credentials = project.import_data if project.import_data
-        if credentials && credentials[:bb_session]
-          token = credentials[:bb_session][:bitbucket_access_token]
-          token_secret = credentials[:bb_session][:bitbucket_access_token_secret]
+        import_data_credentials = project.import_data.credentials if project.import_data
+        if import_data_credentials && import_data_credentials[:bb_session]
+          token = import_data_credentials[:bb_session][:bitbucket_access_token]
+          token_secret = import_data_credentials[:bb_session][:bitbucket_access_token_secret]
           new(token, token_secret)
         else
           raise Projects::ImportService::Error, "Unable to find project import data credentials for project ID: #{@project.id}"

lib/gitlab/fogbugz_import/importer.rb

@@ -31,7 +31,7 @@ module Gitlab
       private
 
       def import_data_credentials
-        @import_data_credentials ||= project.import_data if project.import_data
+        @import_data_credentials ||= project.import_data.credentials if project.import_data
       end
 
       def user_map