Undo: unified undo system w/ linear history

- Use a single undo history for all operations.
- UndoType's are registered and poll the context to check if they
  should be used when performing an undo push.
- Mode switching is used to ensure the state is correct before
  undo data is restored.
- Some undo types accumulate changes (image & text editing)
  others store the state multiple times (with de-duplication).
  This is supported by checking UndoStack.mode `ACCUMULATE` / `STORE`.
- Each undo step stores ID datablocks they use with utilities to help
  manage restoring correct ID's.
  Needed since global undo is now mixed with other modes undo.
- Currently performs each undo step when going up/down history
  Previously this wasn't done, making history fail in some cases.
  This can be optimized to skip some combinations of undo steps.

grease-pencil is an exception which has not been updated
since it integrates undo into the draw-session.

See D3113

1 files changed, 3 insertions, 0 deletions

diff --git a/build_files/cmake/macros.cmake b/build_files/cmake/macros.cmake
index f0cff75c417..3f0868229e2 100644
--- a/build_files/cmake/macros.cmake
+++ b/build_files/cmake/macros.cmake
@@ -559,6 +559,9 @@ function(SETUP_BLENDER_SORTED_LIBS)
 	set(BLENDER_SORTED_LIBS
 		bf_windowmanager
 
+		# needed twice because of text undo
+		bf_editor_util
+
 		bf_editor_space_api
 		bf_editor_space_action
 		bf_editor_space_buttons