git-quiltimport: add --keep-non-patch option

git-am has the --keep-non-patch option to pass -b to
git-mailinfo for keeping subject prefixes intact. Allow
this option to be used with quiltimport as well.

Signed-off-by: Laura Abbott <labbott@redhat.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

Documentation/git-quiltimport.txt

@@ -10,7 +10,7 @@ SYNOPSIS
 --------
 [verse]
 'git quiltimport' [--dry-run | -n] [--author <author>] [--patches <dir>]
-		[--series <file>]
+		[--series <file>] [--keep-non-patch]
 
 
 DESCRIPTION
@@ -56,6 +56,9 @@ The default for the series file is <patches>/series
 or the value of the `$QUILT_SERIES` environment
 variable.
 
+--keep-non-patch::
+	Pass `-b` flag to 'git mailinfo' (see linkgit:git-mailinfo[1]).
+
 GIT
 ---
 Part of the linkgit:git[1] suite

git-quiltimport.sh

@@ -8,6 +8,7 @@ n,dry-run     dry run
 author=       author name and email address for patches without any
 patches=      path to the quilt patches
 series=       path to the quilt series file
+keep-non-patch Pass -b to git mailinfo
 "
 SUBDIRECTORY_ON=Yes
 . git-sh-setup
@@ -32,6 +33,9 @@ do
 		shift
 		QUILT_SERIES="$1"
 		;;
+	--keep-non-patch)
+		MAILINFO_OPT="-b"
+		;;
 	--)
 		shift
 		break;;
@@ -98,7 +102,7 @@ do
 		continue
 	fi
 	echo $patch_name
-	git mailinfo "$tmp_msg" "$tmp_patch" \
+	git mailinfo $MAILINFO_OPT "$tmp_msg" "$tmp_patch" \
 		<"$QUILT_PATCHES/$patch_name" >"$tmp_info" || exit 3
 	test -s "$tmp_patch" || {
 		echo "Patch is empty.  Was it split wrong?"