Document webpack change: Create Cache facade to make it easier to use

[webpack-bot]

A pull request by @sokra was merged and maintainers requested a documentation change.

See pull request: webpack/webpack#11176

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add missing serializers for classes used in test suite

cc @evilebottnawi for terser-webpack-plugin

What kind of change does this PR introduce?
feature

Did you add tests for your changes?
internal plugins now use the new API

Does this PR introduce a breaking change?
yes, compilation.cache is deprecated now

What needs to be documented once your changes are merged?

• The API for access to cache has changed. It's now very similar to the API to get Loggers.

compilation.getCache("MyPlugin") resp. compiler.getCache("MyPlugin") can be used to get a CacheFacade, which is a way to access the cache. compilation.getCache should be preferred of compiler.getCache.

Interface of CacheFacade see here: https://github.com/webpack/webpack/pull/11176/files#diff-d96ec7ae5bb4a0907779f25ed03acb33

There are methods for get and store and promise variants.
There is also a getChildCache(name) method to get a child cache,
and there is a getItemCache(identifier, etag) to get an ItemCacheFacade which allows to access a single item.

The CacheFacade also exposes getLazyHashedEtag to get etags for hashable objects like Sources.

[jeffin143]

Wip

[mitchell-frost]

I would like to work on this issue.

[jeffin143]

I am currently working, if I am not able to you can take it

[mitchell-frost]

I am currently working, if I am not able to you can take it

Okay :)

[Yee1014]

Plz update documentation
It's so baffled ~

[howdyAnkit]

Can anyone tell me how to fix this Deprecation Warning?
@Yee1014 @mitchell-frost @jeffin143
Thanks in Advance.

[howdyAnkit]

people getting those Error it's produced due to the 3rd party plugins are not being supported/might be deprecated if someone's struggling with offline-plugin might need to take a Look into the link below there are few alternatives if you'd like to consider.

NekR/offline-plugin#491