[gimp] Bug 624275 - Image saved from google docs generates a 'gimp-image-set-resolution' error message

[Sven Neumann <neo src gnome org>]

commit ff221e679c2dd17be9cd55d3d980859d656bfccd
Author: Sven Neumann <sven gimp org>
Date:   Tue Jul 13 22:20:15 2010 +0200

    Bug 624275 - Image saved from google docs generates a 'gimp-image-set-resolution' error message
    
    Only set the image resolution if the resolution in the PNG file
    is greater than zero.

 plug-ins/common/file-png.c |    3 ++-
 1 files changed, 2 insertions(+), 1 deletions(-)
---
diff --git a/plug-ins/common/file-png.c b/plug-ins/common/file-png.c
index e906951..1099d24 100644
--- a/plug-ins/common/file-png.c
+++ b/plug-ins/common/file-png.c
@@ -896,7 +896,8 @@ load_image (const gchar  *filename,
       png_uint_32  yres;
       gint         unit_type;
 
-      if (png_get_pHYs (pp, info, &xres, &yres, &unit_type))
+      if (png_get_pHYs (pp, info,
+                        &xres, &yres, &unit_type) && xres > 0 && yres > 0)
         {
           switch (unit_type)
             {