[gtk] (29 commits) Non-fast-forward update to branch wip/baedert/for-master

[Timm Bäder <baedert src gnome org>]

The branch 'wip/baedert/for-master' 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:

  5d1bd9a... window: Replace GtkStyleContext use to get surface transfor
  b075042... cssimage: Add gtk_css_image_to_string()
  948fae6... gl renderer: Avoid some work when rendering border nodes
  f0274e3... GtkCssImageUrl: Implement is_computed()
  929dd6a... cssprovider: Parse selectors without a GList
  56d0d45... cssparser: make a few local variables const
  e07d1fd... Remove gtkutils{.c,private.h}
  a06dea1... render: Remove gtk_render_background_get_clip
  a6e058a... Add pure and const annotations to various functions
  7fc2e1f... renderbackground: Avoid unnecessary work in snapshot_backgr
  e555651... widget: Restructure pick() a bit
  2ee9d7e... dimensionvalue: Add gtk_css_dimension_value_is_zero()
  fe0a612... cssboxes: Try to avoid doing work for rectangular boxes

Commits added to the branch:

  a297129... Add a profiler mark around renderer realization (*)
  7da6fdc... widget: Stop using style context internally (*)
  731ae8f... gskpango: Stop using style context getters (*)
  f1ff699... drag icon: Stop using style context getters (*)
  ac902e6... popover: Stop using style context getters (*)
  0623b00... Merge branch 'style-context-redux' into 'master' (*)
  64e026d... Revert "Ensure icon themes are loaded with other themes" (*)
  03595f9... Fix a scrollbar sizing issue (*)
  3d9e339... lookup stats (*)
  d8144ec... Adwaita: drop the * (*)
  53c22bf... Adwaita: take out an unnecessary rule (*)
  0df0de0... css: Split style into groups (*)
  b4e2df8... Revert "css: Split style into groups" (*)
  7bebc3e... Revert "lookup stats" (*)
  0287e98... window: Replace GtkStyleContext use to get surface transfor
  725eeba... cssimage: Add gtk_css_image_to_string()
  851d4d2... gl renderer: Avoid some work when rendering border nodes
  8a32173... GtkCssImageUrl: Implement is_computed()
  c2ba20b... cssprovider: Parse selectors without a GList
  7108d0b... cssparser: make a few local variables const
  64e613f... Remove gtkutils{.c,private.h}
  e73aecc... render: Remove gtk_render_background_get_clip
  8688668... Add pure and const annotations to various functions
  5bc7621... renderbackground: Avoid unnecessary work in snapshot_backgr
  1337e90... widget: Restructure pick() a bit
  ade8ae3... dimensionvalue: Add gtk_css_dimension_value_is_zero()
  591579b... cssboxes: Try to avoid doing work for rectangular boxes
  e734db4... cssdimensionvalue: Remove an outdated comment
  f5402ea... gsk: Remove some unused defines

(*) This commit already existed in another branch; no separate mail sent