[vala] (5 commits) Non-fast-forward update to branch wip/issue548

[Rico Tzschichholz <ricotz src gnome org>]

The branch 'wip/issue548' was changed in a way that was not a fast-forward update.
NOTE: This may cause problems for people pulling from the branch. For more information,
please see:

 https://wiki.gnome.org/Git/Help/NonFastForward

Commits removed from the branch:

  3d1c706... vala: Search in all interfaces for an implementation match 
  7516906... codegen: Do a proper check before connecting inherited impl
  bad5965... vala: Collect implicit interface implementations
  dd72593... vala: Allow explicit interface methods to be virtual
  df3cee5... vala: Allow get_actual_type() to be used for expected failu

Commits added to the branch:

  99ee759... vala: No need to look further if an implementations was fou
  1cd8f9e... vala: Search in all interfaces for an implementation match 
  c452e32... codegen: Do a proper check before connecting inherited impl
  0c52c5a... vala: Allow explicit interface methods to be virtual
  3c89226... vala: Allow get_actual_type() to be used for expected failu