Merge branch 'jc/diff-from-contents-fix'

The code to squelch output from "git diff -w --name-status"
etc. for paths that "git diff -w -p" would have stayed silent
leaked output from dry-run patch generation, which has been
corrected.

* jc/diff-from-contents-fix:
  diff: make sure the other caller of diff_flush_patch_quietly() is silent

diff --cc diff.c
Simple merge