This patch removes the older handle selection and transformation logic,
which was accessible through user preferences by switching off the
default "simple tweaking" mode in Editing -> Video Sequencer.
There was some initial bugginess with the new handle behavior, hence
the option to revert to legacy mode, but with recent updates this no
longer applies. With the new system, all selection workflows
are still possible -- this just drops older code to make things simpler.
No functional changes intended.
Pull Request: https://projects.blender.org/blender/blender/pulls/140031
fa5178e366