Comment 3 for bug 1483631

Similar output on my home machine (same version of Ubuntu, same LTS enablement stack):

Reading package lists... Done
Building dependency tree
Reading state information... Done
Some packages could not be installed. This may mean that you have
requested an impossible situation or if you are using the unstable
distribution that some required packages have not yet been created
or been moved out of Incoming.
The following information may help to resolve the situation:

The following packages have unmet dependencies:
 libcheese-gtk23 : Depends: libclutter-gtk-1.0-0 (>= 0.91.8) but it is not going to be installed
                   Depends: libcogl15 (>= 1.15.8) but it is not going to be installed
 libcheese7 : Depends: libclutter-gst-2.0-0 (>= 0.10.0) but it is not going to be installed
              Depends: gstreamer1.0-clutter but it is not going to be installed
 libclutter-1.0-0 : Depends: libcogl-pango15 (>= 1.15.8) but it is not going to be installed
                    Depends: libcogl15 (>= 1.15.8) but it is not going to be installed
 libwayland-egl1-mesa-lts-vivid : Depends: libegl1-mesa-lts-vivid (= 10.5.2-0ubuntu1~trusty1) but it is not going to be installed
 xserver-xorg-core-lts-vivid : Depends: libgbm1-lts-vivid (>= 8.1~0) but it is not going to be installed
                               Recommends: libgl1-mesa-dri-lts-vivid (>= 7.10.2-4) but it is not going to be installed
 xserver-xorg-lts-vivid : Recommends: libgl1-mesa-dri-lts-vivid but it is not going to be installed
                          Recommends: libgl1-mesa-glx-lts-vivid but it is not going to be installed
                          Recommends: libegl1-mesa-lts-vivid but it is not going to be installed
                          Recommends: libegl1-mesa-drivers-lts-vivid but it is not installable
                          Recommends: libgbm1-lts-vivid but it is not going to be installed
                          Recommends: libgles2-mesa-lts-vivid but it is not going to be installed
                          Recommends: libgles1-mesa-lts-vivid but it is not going to be installed
                          Conflicts: libegl1-mesa (>= 0~)
                          Conflicts: libgl1-mesa-dri (>= 0~)
                          Conflicts: libgl1-mesa-glx (>= 0~)
                          Conflicts: libglapi-mesa (>= 0~)
                          Conflicts: libgles2-mesa (>= 0~)
E: Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages.