[gtk] (3 commits) Non-fast-forward update to branch wip/baedert/test-cflags

[Timm Bäder <baedert src gnome org>]

The branch 'wip/baedert/test-cflags' 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:

  66b267b... demos/gtk-demo: Add common_cflags to build
  06aa4b6... builder: Make object names a const array
  29cab8f... testsuite/gtk: Add common_cflags to build

Commits added to the branch:

  dc36c21... demos/gtk-demo: Add common_cflags to build
  7789d0e... builder: Make object names a const array
  e1b4050... testsuite/gtk: Add common_cflags to build