bug#183: 23.0.60; !MEM FULL! and pixbuf errors when viewing SVG without a viewBox

[Chong Yidong]

> I have the following super-simple SVG file:
>
>     <?xml version="1.0"?>
>     <!DOCTYPE svg PUBLIC "-//W3C//DTD SVG 1.1//EN"
>         "http://www.w3.org/Graphics/SVG/1.1/DTD/svg11.dtd";>
>     <svg xmlns="http://www.w3.org/2000/svg"; viewBox="-70 -70 140 140">
>       <path d="M 23,-20 A32,32 " />
>     </svg>
>
> When I load this in emacs (using “emacs -q --no-site-file”), I can hit
> C-c C-c and view the file without a problem.
>
> When I remove the viewBox attribute from the svg element, and hit C-c
> C-c, I get the following on the console:
>
> (emacs:30299): GdkPixbuf-CRITICAL **: gdk_pixbuf_get_width: assertion
> `pixbuf != NULL' failed

I've just checked in a fix.  Thanks.