These are the packages that would be merged, in order:

Calculating dependencies... done!

!!! The ebuild selected to satisfy ">=app-misc/tracker-0.12:=" has unmet requirements.
- app-misc/tracker-1.4.1::gentoo USE="exif ffmpeg flac gif gstreamer gtk iso jpeg miner-fs mp3 nautilus networkmanager pdf tiff upower vorbis xml -cue (-eds) -firefox-bookmarks -gsf -iptc (-libav) -playlist -rss -stemmer -test -thunderbird -upnp-av -xmp -xps"

  The following REQUIRED_USE flag constraints are unsatisfied:
    at-most-one-of ( gstreamer ffmpeg )

  The above constraints are a subset of the following complete expression:
    at-most-one-of ( gstreamer ffmpeg ) cue? ( gstreamer ) upnp-av? ( gstreamer ) !miner-fs? ( !cue !exif !flac !gif !gsf !iptc !iso !jpeg !mp3 !pdf !playlist !tiff !vorbis !xml !xmp !xps )

(dependency required by "gnome-extra/nemo-2.8.6::gentoo[tracker]" [ebuild])
(dependency required by "gnome-extra/cinnamon-2.8.6::gentoo" [ebuild])
(dependency required by "gnome-extra/cinnamon" [argument])
(chroot) livecd / # USE="-ffmpeg" emerge --ask gnome-extra/cinnamon

These are the packages that would be merged, in order:

Calculating dependencies... done!

The following mask changes are necessary to proceed:
 (see "package.unmask" in the portage(5) man page for more details)
# required by dev-ruby/racc-1.4.14::gentoo[ruby_targets_ruby23]
# required by dev-ruby/rdoc-4.2.2::gentoo[ruby_targets_ruby20]
# required by dev-lang/ruby-2.0.0_p648::gentoo[rdoc]
# required by dev-ruby/rake-11.1.1::gentoo[ruby_targets_ruby20]
# required by dev-ruby/json-1.8.3::gentoo[-test,-doc,ruby_targets_ruby20]
# required by dev-lang/ruby-2.1.8::gentoo
# required by virtual/rubygems-11::gentoo[ruby_targets_ruby21]
# required by net-libs/webkit-gtk-2.8.5::gentoo
# required by net-libs/gnome-online-accounts-3.16.4.1::gentoo
# required by gnome-base/gvfs-1.24.2::gentoo[gnome-online-accounts]
# required by app-text/evince-3.16.1::gentoo
# required by gnome-extra/sushi-3.16.0::gentoo
# required by gnome-base/nautilus-3.16.2::gentoo[previewer]
# required by gnome-extra/nautilus-tracker-tags-1.4.1::gentoo
# required by app-misc/tracker-1.4.1::gentoo[nautilus]
# required by gnome-extra/nemo-2.8.6::gentoo[tracker]
# required by gnome-extra/cinnamon-2.8.6::gentoo
# required by gnome-extra/cinnamon (argument)
# /usr/portage/profiles/package.mask/funtoo-staging-oleg:
# mask ruby 2.3 until targets also updated to ruby2.3. need tested. Also mask newer eselect ruby, which brings ruby:2.3 support.
=dev-lang/ruby-2.3.0

NOTE: The --autounmask-keep-masks option will prevent emerge
      from creating package.unmask or ** keyword changes.

Would you like to add these changes to your config files? [Yes/No]