[poppler] Poppler 0.26.4 released

[Albert Astals Cid]

Available from
http://poppler.freedesktop.org/poppler-0.26.4.tar.xz

core:
 * CairoOutputDev: Make sure we always push a transparency group in setSoftMaskFromImageMask(). Bug #81624
 * Fix a crash when adding Annotation without contents
 * Improve non-latin characters in inline notes. Bug #65956
 * Don't check for inlineImg twice. Bug #82059
 * printf() -> error()

glib:
 * Return NULL in poppler_annot_get_contents also for empty strings
 * Fix a memory leak when getting text layout and attributes

Cheers,
  Albert