"git diff --ignore-space-change --stat" lists files with only whitespace differences as "changed"

[Matt McCutchen <matt@mattmccutchen.net>]

A bug report: I noticed that "git diff --ignore-space-change --stat"
lists files with only whitespace differences as having changed with 0
differing lines.  This is inconsistent with the behavior without --
stat, which doesn't list such files at all.  (Same behavior with all
the --ignore*space* flags.)  I can reproduce this with the current
"next", af746e4.  Quick test case:

echo ' ' >test1 && echo '  ' >test2 &&
git diff --stat --no-index --ignore-space-change test1 test2

This caused me some inconvenience in the following scenario: I was
reading a commit diff that had a bulk license change in all files
combined with code changes.  I attempted to revert the bulk license
change locally using "sed" to more easily read the code diff, but my
reversion left some whitespace diffs where the original files had
inconsistent whitespace.  So the diffstat after my reversion was
cluttered with these "0" entries.

Regards,
Matt