[gtk] (18 commits) Non-fast-forward update to branch dnd-gestures

[Matthias Clasen <matthiasc src gnome org>]

The branch 'dnd-gestures' 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:

  3f9ddbb... Add (de)serializers for GdkRGBA
  b9566ee... Add a generic callback content provider
  316fa52... colorbutton: Port to GtkDragSource
  bbcfd36... colorswatch: Convert to GtkDragSource
  63ba440... pathbar: Convert to GtkDragSource
  738d897... gtk-demo: Convert the clipboard demo to GtkDragSource
  b0e06b2... iconbrowser: Port to GtkDragSource
  06a50b6... Add another callback-based provider
  ded9fb2... iconview: Port to GtkDragSource
  697eb60... placessidebar: Port to GtkDragSource
  1d19582... treeview: Port to GtkDragSource
  0e837c2... filechooser: Port to GtkDragSource
  23f4454... notebook: Port to GtkDragSource
  f234190... tests: Convert to GtkDragSource
  b03522a... Remove traditional drag source API
  b0b7bec... docs: Mention DND in the migration guide
  0fdfeaa... Move the rest of the drag-source api over
  946a88f... Hook up the GtkDragSource docs

Commits added to the branch:

  f0e4bce... Add (de)serializers for GdkRGBA
  0ad7d01... Add a generic callback content provider
  7333c8e... colorbutton: Port to GtkDragSource
  d35f208... colorswatch: Convert to GtkDragSource
  c0b494a... pathbar: Convert to GtkDragSource
  0da203e... gtk-demo: Convert the clipboard demo to GtkDragSource
  f2e128a... iconbrowser: Port to GtkDragSource
  9f43e86... Add another callback-based provider
  62b5cf1... iconview: Port to GtkDragSource
  6d36e72... placessidebar: Port to GtkDragSource
  4fdad5c... treeview: Port to GtkDragSource
  ab0b576... filechooser: Port to GtkDragSource
  1c9d3e5... notebook: Port to GtkDragSource
  507ed3b... tests: Convert to GtkDragSource
  1cb85f2... Remove traditional drag source API
  51f008e... docs: Mention DND in the migration guide
  5817bb3... Move the rest of the drag-source api over
  ca6805c... Hook up the GtkDragSource docs