In light of discussion about crazy things users do, decided to leave in the former "Temporarily replace..." options, but changed the wording to "Treat missing audio as silence" and warn that the waveform may not show silence.
Added FSCKstatus_SAVE_AUP flag (and returned FSCKstatus_* to being flags). FSCKstatus_SAVE_AUP is set for missing aliased files, so that AudacityProject does a save, fixing a bug where after "Close project immediately...", opening other projects failed in a way that made them incorrectly report missing _data folders, rather than go through Project Check (DirManager::ProjectFSCK).
Decided to continue with the fake-out fixes for missing aliased files and missing SimpleBlockFiles, i.e., writing zeroes instead of replacing with SilentBlockFiles. Replacing is difficult, and there are other places where the zeroes trick is used, e.g., after project check, if there's a disk error, such as a .au being inaccessible in the middle of edits.
Made the "permanent immediately" and "regenerate" options not do a PushState, because they were not possible to Undo.
More comments about things to fix (FIX-ME items this time).
Made AudacityProject::OnShowLog make the log window taller so more likely to show the bottom. The implementation of wxLogWindow makes it hard/impossible to scroll to the bottom.
Fix error of duplicate reports of missing aliased files.
restructuring and renaming for clarity, granularity, and reduction of code duplication
Found and commented on more errors in this code. In the "Close immediately" cases, it doesn't do a real close and that can break subsequent opening of other or the same problematic projects.
Changed several cases where GetDirManager()->ProjectFSCK returned FSCKstatus_CHANGED. These caused a PushState, but Undo could not do anything. Changed corresponding wordings for "Replace missing audio with silence" to say "permanent immediately" instead of "permanent on save", which was incorrect.
Comments about what's wrong with the DirManager::ProjectFSCK "Missing Aliased Files" dialog actions and what to do about it. (More to follow!)
Changed PushState for project repair from "Repair" to "Project Repair" to distinguish from Repair effect.
renames for clarity
2. Save user's preference for enabling linking
3. fix a bug by which changes to global prefs like SWPlaythrough were not
visually reflected in other open projects.
