scm: set supporting all revisions or not at scm level.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@5143 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/models/repository/filesystem.rb

@@ -39,6 +39,10 @@ class Repository::Filesystem < Repository
     'Filesystem'
   end
 
+  def supports_all_revisions?
+    false
+  end
+
   def entries(path=nil, identifier=nil)
     scm.entries(path, identifier)
   end