Channel selection in graph editor was broken by rB3c5620aabd33 because
the selection took into account grease pencil channels. Such channels
are now removed from selection in containers that does not use them (NLA
and Graph Editor).
Grouping was broken from a similar issue. The grouping operation now
completely filters out grease pencil channels since the operator is only
defined for f-curve channels.
Reviewed By: sybren
Maniphest Tasks: T100093
Differential Revision: https://developer.blender.org/D15601
45f483681f