98990f6ba4
`BKE_sequencer_prefetch_get_original_sequence()` didn't look in metas and returned NULL. This caused crash in disk cache that was trying to read seq->name. Add function that will look in meta strips recursively and condition that seq must not be NULL. Reviewed By: brecht Maniphest Tasks: T76033 Differential Revision: https://developer.blender.org/D7597