[glibmm] (7 commits) Non-fast-forward update to branch glibmm-master-use-dllexport

[Chun-wei Fan <fanchunwei src gnome org>]

The branch 'glibmm-master-use-dllexport' 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:

  02758b1... tools: Allow generating Glib:Error class with decorations
  9ccc557... glib/src: Decorate classes and methods with GLIBMM_API
  ecc6dee... build: Do not use gendef.exe for glibmm
  cab6f86... gio/src/*.hg: Mark classes and functions with GIOMM_API
  4c34d9f... gio/giomm/*.h: Mark classes and functions with GIOMM_API
  f294f50... Visual Studio builds: build giomm without gendef
  a546a6d... build: Drop gendef

Commits added to the branch:

  08e7d74... tools: Allow generating Glib:Error class with decorations
  b55811e... glib/src: Decorate classes and methods with GLIBMM_API
  d84be37... build: Do not use gendef.exe for glibmm
  3f66ba7... gio/src/*.hg: Mark classes and functions with GIOMM_API
  c2c96a5... gio/giomm/*.h: Mark classes and functions with GIOMM_API
  cc62858... Visual Studio builds: build giomm without gendef
  0bcdad1... build: Drop gendef