[gtk] (9 commits) ...Merge branch 'ebassi/activate-signal' into 'master'

[Emmanuele Bassi <ebassi src gnome org>]

Summary of changes:

  b3e03fa... Add wrappers for setting the WidgetClass.activate_signal fi (*)
  e5e18dd... Add private method to check activatability (*)
  213024a... Use function setter for WidgetClass.activate_signal (*)
  fde32c5... Use private can_activate() method (*)
  fe9c0db... Add getter for WidgetClass.activate_signal (*)
  3a9cca7... Use WidgetClass.activate_signal getter function (*)
  c352fe9... Move activate_signal to the widget private class data (*)
  d8c9a67... docs: Clarify gtk_widget_activate() (*)
  606cb51... Merge branch 'ebassi/activate-signal' into 'master'

(*) This commit already existed in another branch; no separate mail sent