[gtk] (5 commits) Non-fast-forward update to branch modern-testsuite

[Benjamin Otte <otte src gnome org>]

The branch 'modern-testsuite' 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:

  856154f... reftests: Use the GL renderer
  cb0e32e... tests: Update rendernode test to use textures
  cae1abd... testsuite: Port compare_render() to use textures

Commits added to the branch:

  7d1d3e7... tests: Update rendernode test to use textures
  5a0e078... testsuite: Port compare_render() to use textures
  9589059... reftests: Use 0.6 alpha, not 0.5
  2debc6a... reftests: Use 0.6 instead of 0.5 for alpha
  c4bca35... reftests: Use the GL renderer