Merge branch '4.6' of scm.dev.nokia.troll.no:qt/berlin-staging-1 into 4.6-integration

* '4.6' of scm.dev.nokia.troll.no:qt/berlin-staging-1:
  don't use QKeySequence::mnemonic() after all
  don't use stylesheet for just making labels bold
  remove the rounded extra frame around the main message editor
  add const