[gtk] (6 commits) Non-fast-forward update to branch wip/matthiasc/shortcut-2

[Matthias Clasen <matthiasc src gnome org>]

The branch 'wip/matthiasc/shortcut-2' 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:

  0444098... modelbutton: remove accel poking
  7962ead... modelbutton: Make activatable
  e143147... popover: Implement GtkShortcutManager
  1a495d8... shortcutcontroller: Inject accels into the action muxer
  e2c9f77... popovermenu: Make mnemonics work without Alt

Commits added to the branch:

  375deef... modelbutton: remove accel poking
  f0217ad... modelbutton: Make activatable
  c6e9c2c... popover: Implement GtkShortcutManager
  70ad006... shortcutcontroller: Inject accels into the action muxer
  2c28fe0... popovermenu: Make mnemonics work without Alt
  c8ab3b5... modelbutton: Install accels when inside a popover