Find Widget undo/redo stack doesn't work properly in Chrome

[EmpireJones]

monaco-editor version: 0.14.6(6c8f02b41db9ae5c4d15df767d47755e5c73b9d5) - or whatever https://microsoft.github.io/monaco-editor/index.html is using
Browser: recent Chrome / Chromium, e.g. Version 68.0.3440.106 (Official Build) (64-bit)
OS: Windows, Linux

Steps or JS usage snippet reproducing the issue:

• From Inconsistent undo/redo behavior in Ctrl-F field vscode#27035:

Steps to Reproduce:

Press Ctrl-F
Type something into the field
Select some text in the file being edited
Press Ctrl-F again
Try to undo/redo using keyboard shortcuts

[alexdima]

Let's continue tracking in microsoft/vscode#27035