scm: add test of committer nil at unit changeset test.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@5471 e93f8b46-1217-0410-a6f0-8f06a7374b81

test/unit/changeset_test.rb

@@ -330,9 +330,11 @@ class ChangesetTest < ActiveSupport::TestCase
                         :committed_on => Time.now,
                         :revision     => '123',
                         :scmid        => '12345',
-                        :comments => nil)
+                        :comments     => nil,
+                        :committer    => nil)
       assert( c.save )
       assert_equal "", c.comments
+      assert_equal nil, c.committer
       if c.comments.respond_to?(:force_encoding)
         assert_equal "UTF-8", c.comments.encoding.to_s
       end