Fixes mercurial adapter.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@4541 e93f8b46-1217-0410-a6f0-8f06a7374b81

lib/redmine/scm/adapters/mercurial_adapter.rb

@@ -112,7 +112,7 @@ module Redmine
             cmd << " -r #{identifier_from.to_i}:"
           end
           cmd << " --limit #{options[:limit].to_i}" if options[:limit]
-          cmd << " #{shell_quote path}" if path
+          cmd << " #{shell_quote path}" unless path.blank?
           shellout(cmd) do |io|
             begin
               # HG doesn't close the XML Document...