dirstate.write: don't ignore stat data if mtime is in the future (issue1790) This change narrows the race guard that was introduced by af3f26b6bba4 ("dirstate: ignore stat data for files that were updated too recently") to not discard the _map entry's stat data if the mtime is in the future. Without this change, status locks files having odd mtimes in the future into the 'unset' state, causing needless file compares later (admittedly harmless), but also inflicting highly irritating sticky effects on tools/plugins that directly read .hg/dirstate (e.g. TortoiseHg).