Rails3: scm: darcs: fix error of test_entries_invalid_revision at unit model test
On Rails 3.1, ActiveRecord::HasManyThroughCantAssociateThroughHasOneOrManyReflection error raises. For more details, see r7062.
Rails3: scm: darcs: fix error of test_fetch_changesets_incremental at unit model test
Rails3: scm: mercurial: fix error of test_copied_files at unit model test
Rails3: scm: mercurial: fix error of test_latest_changesets at unit model test
Rails3: scm: mercurial: fix error of test_changeset_order_by_revision at unit model test
Rails3: scm: mercurial: fix error of test_format_identifier at unit model test
Rails3: scm: mercurial: fix error of test_identifier at unit model test
Rails3: scm: mercurial: fix error of test_find_changeset_by_invalid_name at unit model test
Rails3: scm: mercurial: fix error of test_find_changeset_by_name at unit model test
Rails3: scm: git: fix error of test_browse_root at functional test