scm: changing two revision diff text at SCM adapter level (#3724).

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@4698 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/views/repositories/diff.rhtml

@@ -1,4 +1,4 @@
-<h2><%= l(:label_revision) %> <%= format_revision(@changeset_to) + ':' if @changeset_to %><%= format_revision(@changeset) %> <%=h @path %></h2>
+<h2><%= l(:label_revision) %> <%= @diff_format_revisions %> <%=h @path %></h2>
 
 <!-- Choose view type -->
 <% form_tag({:path => to_path_param(@path)}, :method => 'get') do %>