Description of problem:
On a default f7 install `yum clean all' fails with gets errors like:

Error: Error accessing directory //var/cache/yum/fedora/headers, [Errno 2] No
such file or directory: '//var/cache/yum/fedora/headers'

A headers directory has to be created manually for every configured repo before
`yum clean all' will succeed.


Version-Release number of selected component (if applicable):
yum-3.2.1-1.fc7


How reproducible:
Every time so far.


Steps to Reproduce:
1. Install F7
2. yum update or yum check-update
3. yum clean all
  
Actual results:
Fails with above error


Expected results:
Should remove all packages and repo data files.


Additional info:
This is a regression from yum-3.0.6-1.fc6 where `yum clean all' works fine even
if the headers directory is removed - it gets recreated.