b7049a7c04
Split the legacy Action handling code of `action_fcurve_ensure()` into a new function `action_fcurve_ensure_legacy()`. This makes it possible for unit tests to explicitly create a legacy Action for testing, regardless of the 'Slotted Actions' experimental feature flag. When we drop that flag, the unit tests that explicitly test legacy behaviour will keep running. Pull Request: https://projects.blender.org/blender/blender/pulls/128892