Add TextDrive.getFilesToSave to externs to fix autosave.
Add TextDrive.getFilesToSave to externs to fix autosave.

modulexcite/text-app,l3dlp/text-app,modulexcite/text-app,codex8/text-app,codex8/text-app,l3dlp/text-app,l3dlp/text-app,modulexcite/text-app,wearefractal/extension-boiler,zkendall/WordBinder,zkendall/WordBinder,zkendall/WordBinder,codex8/text-app