Reuse new gtkfilechooser Search feature in Nautilus

[Luca Ferretti <elle uca libero it>]

In the last weeks a feature have landed in GTK+ trunk: the availability
of a "search" section in filechooser. See this[1] and this[2] posts from
Emanuele Bassi - and of course gtk+ sources :-)

IMHO Nautilus 2.20 should import the search engine code from gtk: both
nautilus and gtk support beagle and tracker search engine, but gtk+
don't depend on them at compile time. Using Emanuele's words: 

        "There’s no hard dependency on Beagle or Tracker: the libraries
        are opened using g_module_open() if they are found installed on
        your system, otherwise it’ll all fall back to the simple search
        backend"



[1] http://log.emmanuelebassi.net/archives/2007/05/company-calls/
[2]
http://log.emmanuelebassi.net/archives/2007/05/company-calls-epilogue/