add compareSubstring, compareSubstringIgnoreCase and adopt for search tree so that it will be fit for case-in-sensitive compare, https://github.com/microsoft/vscode/issues/93368

allow compareIgnoreCase to operate on substrings, touches on https://github.com/microsoft/vscode/issues/93368

add es6 deprecation messages to some utils, remove duplicated utils, https://github.com/microsoft/vscode/issues/90676

This reverts commit 30886e2f, reversing
changes made to 525f1e47.

Removing these since strict null checking should catch the a compile time. If there are any places where undefined is getting incorrectly passed in, we'd like to know about these

Fix #80455

and remap \u{1234} for rg
Fix #62416, fix #61746

- make it unlikely that a new view instance would accept a view zone id from a previous view instance
- remove that the find widget removes a view zone id from another view
(fixes #71745)

Try to better support handle of unicode in markdown by using a word definition that use unicode character class

Fixes #15177

We compile using the alwaysStrict flag so these directives are not needed

This part removes most `use strict` directives that are right after the file header

Fixes #59757