[MacPorts] #65859: gnome cpp libs: all are outdated; update to latest compatible releases

[MacPorts]

#65859: gnome cpp libs: all are outdated; update to latest compatible releases
-------------------------+-------------------------------------------------
 Reporter:  mascguy      |      Owner:  mascguy
     Type:  defect       |     Status:  assigned
 Priority:  Normal       |  Milestone:
Component:  ports        |    Version:  2.7.2
 Keywords:               |       Port:  atkmm glibmm gtkmm gtkmm3 cairomm
                         |  pangomm
-------------------------+-------------------------------------------------
 Presently the various libs related to C++ bindings for `glib2`,
 `gtk2/gtk3`, etc - along with related ones like `cairomm` and `pangomm` -
 are all outdated. Update them to the latest possible releases, based on
 the current version of `glib2` (presently 2.70.x).

 In addition to bringing them up to parity with upstream, these updates may
 also fix some existing issues with some ports. And CherryTree in
 particular may benefit, per issue:65743

 Of note, since the latest releases of these have bumped the API version -
 from 2.4 to 2.68 for `glibmm`, for example - that may require creation and
 support of legacy releases using the previous API rev. Particularly for
 old or outdated ports, which simply won't work with the newest APIs.

 Net-Net, this rollout will have to be carefully coordinated and
 choreographed. And to avoid potential widespread breakage, all dependents
 will need to be well-tested - and updated, if necessary - prior to
 rollout.

-- 
Ticket URL: <https://trac.macports.org/ticket/65859>
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