Massive replace makes window unresponsible and then crashes the window

[kieferrm]

Testing #8184.

• VSCode Version: Insiders 6/29
• OS Version: Windows

Steps to Reproduce:

1. Use a large code base such as the vscode repo
2. "View: Show Search"
3. Expand Search
4. Enter a as search string
5. Enter b as replace string
6. Press Enter
7. Wait for the search to finish
8. Press Replace All

Then:

Eventually the window will crash.

We should have safeguards against this kind of abuse. Independently, the window should never become unresponsive.

[sandy081]

There are two parts for this issue

• Search: did we loose the upper limit for search results? #8369 - We had the limitation for max search results, which was taken off. I kept it back again. We need to investigate / profile before taking the limitation off
• Replace: is very slow for many results #8371 - Making replace faster

[sandy081]

With above fixes there wont be crash or slowness. Created investigation item #8563 to lift the limitation