[gtk] (18 commits) ...Merge branch 'wip/otte/dnd' into 'master'

[Benjamin Otte <otte src gnome org>]

Summary of changes:

  d9fa839... testsuite: Use g_assert() in tests (*)
  fdb39b0... treeview, iconview: Don't return the drop target (*)
  b799bc5... textview: Move drop scrolling to drop motion controller (*)
  b64a027... notebook: Make dnd page switching a drop controller (*)
  f4ac747... placessidebar: Don't use the GdkDrag (*)
  a411959... droptarget: Redo (*)
  3f7b401... gtk-demo: Add a simple peg solitaire DND demo (*)
  c3fb6ca... colorswatch: Switch to dragged color during dnd (*)
  7cd728a... gdk: Make gdk_drop_status() take preferred action (*)
  9efc4e6... dragicon: Add GtkDragIcon::child (*)
  03882e1... dragicon: Change how to acquire drag icons (*)
  b2c3e39... contentformats: Constify some functions (*)
  2a69782... dragicon: Add gtk_drag_icon_create_widget_for_value() (*)
  e7db386... dnd: Don't create custom color drag icons (*)
  f4a00e7... calendar: Use a drag source (*)
  f5fda3a... themes: Set proper foreground color for DND icons (*)
  0e72adf... drop: Remove unused convenience APIs (*)
  47230f1... Merge branch 'wip/otte/dnd' into 'master'

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