Whenever the display list gets regenerated, we need to restore the
code list view scroll position to the previous location in the file.
This gets tricky when multiple lines are appearing or disappearing.
We were saving the file offset of the line, but that works poorly
when there's a multi-line comment associated with that offset,
because we end up scrolling to the top of the comment whenever any
part of the comment is at the top of the screen.
We now track the file offset and the number of lines we were from
the top of that offset's content. This works well unless we remove
a lot of lines. If the adjusted line index would put us into a
different file offset, we punt and just scroll to the top of the item.
Also, fix a crasher in Edit Note.
Also, fix behavior when the list shrinks while a line near the end
of the file is selected.
Also, change a few instances of "Color.FromArgb(0,0,0,0)" to use a
common constant.
Mostly a straight copy & paste of the files. The only significant
change was to move the localizable strings from Properties/Resources
(RESX) to Res/Strings.xaml (Resource Dictionary). I expect a
number of strings will no longer be needed, since WPF lets you put
more of the UI/UX logic into the design side.
I also renamed the namespace to SourceGenWPF, and put the app icon
into the Res directory so it can be a resource rather than a loose
file. I'm merging the "Setup" directory contents into the main app
since there wasn't a whole lot going on there.
The WPF Color class lacks conversions to/from a 32-bit integer, so
I added those.
None of the stuff is wired up yet.
