Comment 4 for bug 1359558

As Taihsiang mentioned, the root couse is bug 1318084. The issue here is that plainbox-provider-checkbox depends on glmark2-es2, which in turn requires packages providing libgles2-mesa and libglapi-mesa. The direct packages (named libgles2-mesa and libglapi-mesa) are older and do not take into consideration the updated X stack for 12.04 point releases, so in essence they try to downgrade the X stack back to 12.04.0.

The correct way to satisfy these dependencies with the enablement stacks is with the stack-specific packages that provide (via virtual package) those services. For 12.04.5, *before* installing checkbox, do this:

apt-get install -y --force-yes libgles2-mesa-lts-trusty libegl1-mesa-lts-trusty

It's not easy to solve on the packaging side (i.e. I can't really make apt-get install plainbox-provider-checkbox work correctly) because apt-get has no provision for this, and the fact that glmark2-es2 is not a directly-installed package but a recommends of our packages also complicates things.

Other than the workaround I suggested, the alternative we will explore is making the glmark2-es2 dependency arch-specific. glmark2-es2 should run only on arm systems, not x86, so by ensuring it doesn't have that dependency on x86, we can eliminate this problem.