gitweb/lib - Regenerate entry if the cache file has size of 0
If the file representing cache entry has size 0 (in bytes), the cache
entry is considered invalid, regardless of its freshness, even if cache
expiration is turned off.
[jh: This is a quick, and thankfully easy, check to regenerate the
cache if the resulting file is of size 0. This *SHOULDN'T* happen,
but it is possible that it could and thus adding the check.]
Based-on-commit-by: John 'Warthog9' Hawley <warthog9@eaglescrag.net>
Signed-off-by: Jakub Narebski <jnareb@gmail.com>