UI Code Quality: General refactor of Outliner View Layer display mode creation

See https://developer.blender.org/D9499.

* Turn functions into member functions (makes API for a type more obvious &
  local, allows implicitly sharing data through member variables, enables order
  independend definition of functions, allows more natural language for
  function names because of the obvious context).
* Move important variables to classes rather than passing around all the time
  (shorter, more task-focused code, localizes important data names).
* Add helper class for adding object children sub-trees (smaller, more focused
  units are easier to reason about, have higher coherence, better testability,
  can manage own resources easily with RAII).
* Use C++ iterators over C-macros (arguably more readable, less macros is
  generally preferred)
* Add doxygen groups (visually emphasizes the coherence of code sections,
  provide place for higher level comments on sections).
* Prefer references over pointers for passing by reference (makes clear that
  NULL is not a valid value and that the current scope is not the owner).

1 files changed, 2 insertions, 1 deletions

diff --git a/source/blender/editors/space_outliner/outliner_tree.c b/source/blender/editors/space_outliner/outliner_tree.c
index 874d35112a5..84b59da26c1 100644
--- a/source/blender/editors/space_outliner/outliner_tree.c
+++ b/source/blender/editors/space_outliner/outliner_tree.c
@@ -2321,7 +2321,8 @@ void outliner_build_tree(Main *mainvar,
   outliner_tree_view_destroy(&space_outliner->runtime->tree_view);
 
   TreeSourceData source_data = {.bmain = mainvar, .scene = scene, .view_layer = view_layer};
-  space_outliner->runtime->tree_view = outliner_tree_view_create(space_outliner->outlinevis);
+  space_outliner->runtime->tree_view = outliner_tree_view_create(space_outliner->outlinevis,
+                                                                 space_outliner);
   space_outliner->tree = outliner_tree_view_build_tree(
       space_outliner->runtime->tree_view, &source_data, space_outliner);