SplitView Architecture Tasking

Here's a proposed guide to breakup the story into smaller arch pieces:

1. Opportunistic Cleanup

   • _openInlineWidget
   • _toggleInlineWidget
   • _showCustomViewer
   • closeInlineWidget
   • getInlineEditors
   • getFocusedInlineWidget

2. Migrate WorkingSet Management to EditorManager

   • Code new WorkingSet APIs in EditorManager
   • Move serialization code from DocumentManager
   • add deprecation warnings to old APIs
   • add bridge to new API from old APIs
   • Write issues for extensions still using old APIs
   • Migrate core and default extension code to new WorkingSet API
   • Notify extension authors
   • Update Unit tests

3. RefactorFile.commands from DocumentCommandHandlers into FileCommandHandlers (depends on #2)

   • Move FILE.xxx and call EditorManager functions

4. Deprecate getWorkingSet (depends on #2)

   • Migrate all core instances (7)
   • Migrate all core extension instances
   • Notify extension authors
   • Add deprecation warning
   • Unit tests

5. Migrate DocumentManager.getCurrentDocument (depends on #2)

   • Notify all extension authors

6. Implement EditorManager code for 1x2 editors

   • tease apart editor calls directly and move to editor
   • implement basic layout
   • implement working set view create
   • implement editor create
   • update serialization code
   • working set context and gear menus
   • close others extension
   • test git extension (notfy zaggino)
   • Unit tests

7. Add support for images in working set

   • create custom viewer
   • implement all file based commands to work on images
   • Implement all working set commands for images
   • Unit tests

8. Implement UI for split view (depends on 6)

   • implement core changes to direct splits, etc...

9. Final cleanup and Polish.