Select All Files in Commit Window Doesn't Respect Filter

Summary

When staging files for a commit with a filter (e.g. "NLM_" for files starting with prefix "NLM_"), the select all files toggle doesn't respect the filter.

Steps to Reproduce

1. Change a couple files
2. Enter a file so that only some of those files are shown in unstaged files list
3. Click "Unstage Files" checkbox
4. Clear Filter
   See attached screen recording for STRs in action.

Expected Outcome

Only the files shown while filter enabled are staged.

Actual Outcome

All files are staged.