[Tracker] [PATCH] fix tracker-extract-pdf crash with stable poppler

["Alexandre Rostovtsev" <tetromino gmail com>]

Hi.
The stable version of poppler does not support the metadata property,
so if metadata_xml is uninitialized, then g_object_get( document,
"metadata", &metadata_xml, NULL) followed by use of metadata_xml leads
to crashes:

(process:20721): GLib-GObject-WARNING **: IA__g_object_get_valist:
object class `PopplerDocument' has no property named `metadata'
XML parsing failure
*** glibc detected *** ./tracker-extract: free(): invalid pointer:
0x00007fffdbe7fbb0 ***
Aborted

Solution is to initialize metadata_xml (and for good programming
practice, any gchar*) before passing to g_object_get.

Patch attached.

-Alex Rostovtsev.

Attachment: tracker-670-poppler-crash.patch
Description: Binary data