Blacklist media-libs/mesa package
Blacklist media-libs/mesa package

Add media-libs/mesa to the blacklisted list so we can pull in upstream
changes without uprevving the ebuild and breaking the bots. This also
allows us to do lockstep libdrm upgrades when needed.

BUG=chromium-os:31134
TEST=None

Change-Id: Ic81418c265868abfe2321a5ba1b404be5b6f562e
Reviewed-on: https://gerrit.chromium.org/gerrit/23261
Reviewed-by: David James <f231dc574bbeb62604660cbc162d1b8642a0a3af@chromium.org>
Commit-Ready: Sean Paul <f9352ecf3e2294bdb914c99cca8d12601acec118@chromium.org>
Tested-by: Sean Paul <f9352ecf3e2294bdb914c99cca8d12601acec118@chromium.org>
Reviewed-by: Stéphane Marchesin <e16f69845633a0cf74affe1e5a677caa6296c937@chromium.org>

chadversary/chromiumos.chromite,coreos/chromite,bpsinc-native/src_third_party_chromite,bpsinc-native/src_third_party_chromite,bpsinc-native/src_third_party_chromite,coreos/chromite,zhang0137/chromite,chadversary/chromiumos.chromite,zhang0137/chromite,zhang0137/chromite,coreos/chromite