Accept an object as mode

[karamosky]

What's in this PR?

Accept mode as object or string

List the changes you made and your reasons for them.

React-ace forces me to use a syntax mode defined in this namespace: "ace/mode/?" whereas Ace setMode can accept both strings and objects. It allows us to inject a custom Ace.SyntaxMode for example or use another defined in another namespace with:

{ path: "path/to/mode" }

References

Ace repo:

var JavaScriptMode = ace.require("ace/mode/javascript").Mode;
editor.session.setMode(new JavaScriptMode());

[securingsincity]

Thanks @karamosky this is live in v9.3.0