textconv: make the API public

The textconv functionality allows one to convert a file into text before
running diff. But this functionality can be useful to other features
such as blame.

Signed-off-by: Axel Bonnet <axel.bonnet@ensimag.imag.fr>
Signed-off-by: Clément Poulain <clement.poulain@ensimag.imag.fr>
Signed-off-by: Diane Gasselin <diane.gasselin@ensimag.imag.fr>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/diff.c b/diff.c
index 494f560..b4a830f 100644
--- a/diff.c
+++ b/diff.c
@@ -43,10 +43,6 @@
 	GIT_COLOR_NORMAL,	/* FUNCINFO */
 };
 
-static void diff_filespec_load_driver(struct diff_filespec *one);
-static size_t fill_textconv(struct userdiff_driver *driver,
-			    struct diff_filespec *df, char **outbuf);
-
 static int parse_diff_color_slot(const char *var, int ofs)
 {
 	if (!strcasecmp(var+ofs, "plain"))
@@ -1629,7 +1625,7 @@
 		options->b_prefix = b;
 }
 
-static struct userdiff_driver *get_textconv(struct diff_filespec *one)
+struct userdiff_driver *get_textconv(struct diff_filespec *one)
 {
 	if (!DIFF_FILE_VALID(one))
 		return NULL;
@@ -4002,9 +3998,9 @@
 	return strbuf_detach(&buf, outsize);
 }
 
-static size_t fill_textconv(struct userdiff_driver *driver,
-			    struct diff_filespec *df,
-			    char **outbuf)
+size_t fill_textconv(struct userdiff_driver *driver,
+		     struct diff_filespec *df,
+		     char **outbuf)
 {
 	size_t size;