... in the first label track.
Problem was calling wxTextCtrl::AppendText once per label, per push of undo
stack, each call causing event handling.
Now call it only once per push.
We can't go to 3.0.1 yet as there are still build issues on
Linux and OSX. You can get Windows to build, but there's
still some display issues.
These changes should work with wxWidgets 2.8.12 as well, so
we can take our time to get things working properly before
switching over.
This change is believed to be a direct refactoring that does not change functionality. It paves the way for more complex kinds of selection, such as selections involving frequency as well as time. It also reduces risk of left and right edges being swapped in future code using SelectedRegion, as the default is to swap on assignment if needed.
