before this change:
1) switch to 'custom' meter point,
2) deactivate meter processor.
-> meters does not run regardless of meter-point
-> meter can only be re-nabled in 'custom' mode
..and continue to calculate fall-off in
audio-cycle (rather than UI thread)
TODO: check if this works properly when switching
between audio/midi meter modes on a midi-track.
One of the motivations to always reset meters when the
meter-point changes was to resolve peak-hold & fall-off
issues when a midi-meter replaces an audio-meter and vice
versa.
TODO: shadow should really be 'behind'. ie save color,
stroke_preserve() shadow, paint text-layout with saved color
and eventually cairo_new_path() reset the path...
gtkmm2ext/keyboard.cc has a special case to emit a signal on the key-up of
the modifier key used to adjust track heights in conjunction with the
scroll wheel, so that the same track continues to be resized even when
it's shrunk to no longer be under the mouse cursor. However, this code
assumed that the modifier key for this was <Shift>.
Fix it to use the event->state bit corresponding to
ScrollZoomVerticalModifier instead, and rename the relevant functions to
clarify that it's the 'zoom vertical' modifier key they're dealing with.
Partially fixes#5610.
when using ImportDistinctChannels, correctly name regions so that playlists for each channel/track
are also named differently, and thus reloaded properly when the session is reloaded.
