Results count does not get updated in Find

Nature of issue?

• Found a bug

Details about the bug:

• Web browser and version: 88.0.1 (64-bit)
• Operating System: Windows 10

Steps to reproduce:

• In the Find window, change the input field and the search options so that the number of occurrences in the editor varies.
  Actual result: The label with the number of occurrences does not get updated.
  Expected result: The label should be consistent with the number of highights in the editor.
• Still in the Find window, press Enter in the input field, or click the previous/next arrows
  Resuts: Now, but only now, the result count gets updated.

Extra confusion comes from the fact that some clickable controls in Find make the count update (the previous/next arrows), but other clickable controls do no (search options like case sensitivity or "only whole words").

Attaching a screen grab to illustrate.

https://user-images.githubusercontent.com/22029901/117534132-741cfa00-aff0-11eb-8d59-8d1ff2d53230.mp4

Start by reproducing the issue in the Find window: change the search input and options, then compare the result-count label with the highlighted occurrences in the editor. Trace the Find window's count-update behavior for input, search-option changes, Enter, and navigation controls; done means the label stays consistent after each relevant change.