Reduce number of StrictMode warnings

[jeffchheng]

To alleviate some of #6060.

cWRP was easy enough to change. Some instances of cWM weren’t quite as easy due to the legacy context API and having no familiarity with it.

Still, I was able to run this symlinked to my company’s app and see at least a reduction in StrictMode errors with no change in app functionality.

Also added a StrictMode test for each component, skipped if it wasn’t fixed yet.

[mjackson]

Thanks for the PR, @jeffchheng :)

I did some major refactoring over the past week and eliminated all the deprecated componentWill methods in the process, so we won't need this anymore. You can see some of my commits here and here.

My apologies for not guiding you through this work so we could get this merged, but it was a little tricky due to the changes in the context API and I wanted to make sure I understood all of the implications of making this change, so I decided to do it myself. You can expect this to be published in our next beta release sometime this week. 😅

[jaredpalmer]

Just a note here. This is unfortunately not enough to work within Suspense. We still need to get rid of all usage of the legacy context API for RR4 to work within <StrictMode>.

[mjackson]

I'm going to cherry-pick the <StrictMode> tests from this PR under a feature flag so we can make sure we don't print any errors in strict mode.

[mjackson]

Sorry, I didn't mean to re-open. I'll go ahead and cherry-pick those tests myself.