[tracker] tracker-extract: Don't pass known-NULL pointer in PNG error paths

[Carlos Garnacho <carlosg src gnome org>]

commit 3bd13a7058f5f46676e0e1e854a11a42e19a50c8
Author: Carlos Garnacho <carlosg gnome org>
Date:   Wed Dec 14 20:01:44 2016 +0100

    tracker-extract: Don't pass known-NULL pointer in PNG error paths
    
    The info_ptr is checked to be NULL, no need to pass it to the
    png_destroy_read_struct() function. Spotted through a false "c&p
    mistake" report from Coverity further down, in the error paths
    where info_ptr is actually non-NULL and needs freeing.

 src/tracker-extract/tracker-extract-png.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)
---
diff --git a/src/tracker-extract/tracker-extract-png.c b/src/tracker-extract/tracker-extract-png.c
index 2bf13cb..95ae299 100644
--- a/src/tracker-extract/tracker-extract-png.c
+++ b/src/tracker-extract/tracker-extract-png.c
@@ -632,7 +632,7 @@ tracker_extract_get_metadata (TrackerExtractInfo *info)
 
        info_ptr = png_create_info_struct (png_ptr);
        if (!info_ptr) {
-               png_destroy_read_struct (&png_ptr, &info_ptr, NULL);
+               png_destroy_read_struct (&png_ptr, NULL, NULL);
                tracker_file_close (f, FALSE);
                return FALSE;
        }