[gtk/wip/baedert/for-master] (40 commits) ...Implement diff() for color matrix nodes

[Timm Bäder <baedert src gnome org>]

Summary of changes:

  fcbc972... print-editor: Fix crash (*)
  fede7cd... gtk-demo: Fix expander demo (*)
  a02c588... gtk-demo: InfoBar is not a GtkBox anymore (*)
  8dfdd68... Merge branch 'print-editor-new-crash' into 'master' (*)
  10813dd... Merge branch 'gtk-demo-expander-fix' into 'master' (*)
  ab148c0... Merge branch 'wip/baedert/for-master' into 'master' (*)
  fa784aa... Cosmetics (*)
  cbc2493... Update Japanese translation (*)
  d0c54c1... Update Japanese translation (*)
  3bf6bda... demo: Remove double borders from the treeview (*)
  69ee1e1... Adwaita: use thinner arrows for navigation (*)
  4ed062e... Merge branch 'wip/jimmac/menu-styling-adjustments' into 'ma (*)
  51ec0f1... Merge branch 'wip/exalm/ocd' into 'master' (*)
  aae0770... scale: Make the area around the trough clickable (*)
  deef018... tests: Drop testtoolbar2 (*)
  c3aeac1... tests: Drop testpixbuf-scale (*)
  1420e84... tests: Drop testicontheme (*)
  604f4cf... tests: Drop testcolorchooser2 (*)
  b0fcf64... tests: Drop testbox (*)
  d1134e7... Merge branch 'usable-scales' into 'master' (*)
  b8e905e... tests: Drop testcolorchooser (*)
  a375c41... tests: Drop testfontchooser (*)
  dc8c371... tests: Drop testexpander (*)
  25577e4... tests: Drop testnoscreen (*)
  8e6ec0b... tests: Fix scrolling performance test (*)
  10be40a... scrolledwindow: Fix swapping out child (*)
  e87bc3d... gtk-demo: Plug a memory leak (*)
  15e7bf5... Merge branch 'matthiasc/for-master' into 'master' (*)
  c165890... Merge branch 'tests-cleanup' into 'master' (*)
  cea6613... flowbox: Make the children focusable again (*)
  4c8688b... inspector: Disable recursive inspection (*)
  e9d9664... gtk-demo: Don't overdraw the fishbowl (*)
  ce949c0... widget-factory: Cosmetic changes (*)
  7ef51da... listbox: Don't steal focus-on-click (*)
  7915e99... listbox: Make Shift-Tab work again (*)
  33011cc... flowbox: Avoid a crash in measure() (*)
  69ab403... flowbox: Avoid an assertion in snapshot() (*)
  378cca7... Add a test for a flowbox crash (*)
  9f4e7b1... Merge branch 'matthiasc/for-master' into 'master' (*)
  5ccc5a6... Implement diff() for color matrix nodes

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