rails/rails — pull request #9713 by imanel (2013-03-14 08:20:38+00:00)
Title: Handle conditional get in live requests

This will prevent error when using stale on live stream(issue #9636)

Test application: https://github.com/imanel/liveStale

**Rationale**: sometimes we want to use stale on longer actions(like live ones) and currently it is impossible. With this patch ETag will be set for actions that are not using `stream.write`, which is probably expected behavior.