Outliner: Refactor outliner tree-hash interfaces with C++

- Turn storage into an object with "automatic" memory management (RAII)
  so freeing is implicit and reliable.
- Turn functions into member functions, to have the data and its
  functions close together with controlled access that increases
  encapsulation and hiding implementation details.
- Use references to indicate null is not an expected value.
- Related minor cleanup (comments, use const etc.)

Couldn't spot any changes in performance.

1 files changed, 1 insertions, 2 deletions

diff --git a/source/blender/editors/space_outliner/outliner_utils.cc b/source/blender/editors/space_outliner/outliner_utils.cc
index 9c1425befdd..2ce017f4f64 100644
--- a/source/blender/editors/space_outliner/outliner_utils.cc
+++ b/source/blender/editors/space_outliner/outliner_utils.cc
@@ -184,8 +184,7 @@ TreeElement *outliner_find_tse(SpaceOutliner *space_outliner, const TreeStoreEle
   }
 
   /* Check if 'tse' is in tree-store. */
-  tselem = BKE_outliner_treehash_lookup_any(
-      space_outliner->runtime->treehash, tse->type, tse->nr, tse->id);
+  tselem = space_outliner->runtime->tree_hash->lookup_any(tse->type, tse->nr, tse->id);
   if (tselem) {
     return outliner_find_tree_element(&space_outliner->tree, tselem);
   }