[gtk] (10 commits) Non-fast-forward update to branch wip/otte/float-textures

[Benjamin Otte <otte src gnome org>]

The branch 'wip/otte/float-textures' 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:

  f61a75f... texture: Add GdkMemoryConversion private enum
  25ae53e... texture: Add gdk_texture_download_float()
  3021884... memorytexture: Add support for HDR formats
  9375886... testsuite: Overhaul memorytexture test
  5b4694c... testsuite: Rework memorytexture test some more

Commits added to the branch:

  202e1f1... gltexture: release() to a texture, not a cairo_surface
  6783faf... texture: Add GdkMemoryConversion private enum
  6f33c8d... texture: Add gdk_texture_download_float()
  1837c7b... memorytexture: Add support for HDR formats
  e5913a3... testsuite: Overhaul memorytexture test
  8e9ffaa... testsuite: Rework memorytexture test some more
  863c726... testsuite: Add tests uploading the memorytextures
  88f84d9... gdk: Deprecate gdk_cairo_draw_from_gl()
  30470fd... testsuite: Add memory test support for OpenGL up/downloads
  a4daa77... gltexture whatever HELP: CLEAN THIS UP!