(and noted on irc a few weeks ago)
When using svnsync to migrate a repository, sometimes a connection might break
due to network problems.
The new in 1.7 code then tries to send the same request and continue where the
connection broke down.
This user got two separate issues, that probably have the same root cause:
* The assertion that the content-length had shrunk triggered.
* The revision number check failed as the target repository has a revision to
much, while only a single svnsync process used the repository.
Eventually the sync succeeded after a few attempts (and switching to the much