[yocto] Switch to GTK+3

[Gary Thomas]

I just tried a build from the latest Poky/Yocto master (2a85038dd)
Overall, I think the switch to GTK+3 is an improvement, but I have
a number of [usability] questions:

* I built firefox from meta-browser and noticed that on my touch only
device, it does not automatically pop-up the keyboard.  However, epiphany
does.  I've only done a little testing but that's what I observed.  Not
having this happen "on demand" (i.e. when a text field has the focus)
will make using a full screen application impossible on this hardware.

* Also on firefox, I can't seem to get the vertical scrollbar to work.
Again, with epiphany it at least works.

* The system also doesn't seem to play very nice with my GPU enhanced
i.MX6 and causes the SoC to overheat (didn't happen with GTK+2).  Makes
it rather unusable as well.

* gtk-play ran my 1GB system out of memory, just starting up :-(  This
caused a complete system lockup & I could not even restart the X server.
This application also seemed to run quite well with GTK+2

* There also seem to be a continuous stream of messages like these on the console:

   GLib-GIO-Message: Using the 'memory' GSettings backend.  Your settings will not be saved or shared with other 
applications.
   Gtk-Message: GtkDialog mapped without a transient parent. This is discouraged.

I know that these firefox vs. epiphany vs. chome vs. ... questions
are not really the responsibility of Yocto or OE-core, but it does
trickle down to those of us trying to use this framework.

Many thanks for any thoughts

n.b. I was torn what mailing list to use for this - it's tightly
tied to OE-core, but isn't really about patches or changes, more
about philosophy.  If the OE-core list is more appropriate, please
move the replies there.

-- 
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Gary Thomas                 |  Consulting for the
MLB Associates              |    Embedded world
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