Merge branch 'sk/spawn-less-case-insensitively-from-grep-O-i' into maint

"git grep -O" to show the lines that hit in the pager did not work
well with case insensitive search.  We now spawn "less" with its
"-I" option when it is used as the pager (which is the default).

* sk/spawn-less-case-insensitively-from-grep-O-i:
  git grep -O -i: if the pager is 'less', pass the '-I' option

Author: gitster

builtin/grep.c

@@ -874,6 +874,9 @@ int cmd_grep(int argc, const char **argv, const char *prefix)
 		if (len > 4 && is_dir_sep(pager[len - 5]))
 			pager += len - 4;
 
+		if (opt.ignore_case && !strcmp("less", pager))
+			string_list_append(&path_list, "-I");
+
 		if (!strcmp("less", pager) || !strcmp("vi", pager)) {
 			struct strbuf buf = STRBUF_INIT;
 			strbuf_addf(&buf, "+/%s%s",