Remove deprecated methods in 4.0.0

[mgol]

Description

We've deprecated some methods in 3.x (like jQuery.camelCase), we should remember to remove them all in 4.0. Looking at deprecated.js should be a good start; other APIs to remove:

• jQuery.cssProps.
• jQuery.cssNumber (removed in CSS: Don't automatically add "px" to properties with a few exceptions #4055).

Link to test case

[ShashankaNataraj]

@mgol I want to submit a PR for this.. Is this issue still relevant?

[mgol]

@ShashankaNataraj It is, though we're not working on jQuery 4.0 yet. You can submit a PR, though. You'd need to look at each of the deprecated APIs; some are in deprecated.js, some are only deprecated in docs: 3.0 & 3.3 and some may only have an API issue created but the deprecations are not documented yet: https://github.com/jquery/api.jquery.com/issues?utf8=%E2%9C%93&q=is%3Aissue+is%3Aopen+deprecate.

For ones that have API docs tickets, we should first document the deprecation before we remove it on master; we're a little understaffed when it comes to content sites (like api.jquery.com) so especially there help would be appreciated. Thanks!

[mgol]

PR: #4364