Make time_zone parameter properly volatile

[timroes]

Summary

Fixes #35494

In #34795 we wanted to make the time_zone parameter of date_histogram volatile and no longer save it in the saved object (since that was a severe bug). Unfortunately the serialize method of an aggregation param is called from AggConfig.toJSON which was used in Vis.getSerializableState and Vis.getCurrentState to clone those objects, thus the time_zone was actually also removed on the way to the query and the timezone the rollup plugin set didn't effect the query.

This PR now moves all the logic for the time_zone parameter into its write method (which is used purely when writing out the DSL for that parameter). This method will now check the typeMeta on the index pattern itself (which is set for roll up indexes). If that has a time_zone it's used. Otherwise the time_zone from the kibana settings is used. You can also still technically set the time_zone explicitly, which we currently don't use anywhere (but might be exposed later on in the visualization expression). This means the parameter itself will always be undefined in places it's passed around in the code, and really only be taken care of once written to DSL.

Since the bug has not yet been released I marked this as skip for the release notes.

Testing:

This PR should fix #35494 and now allow to visualize over a rolled-up index pattern while your Kibana is in a different time_zone then the index was rolled up. Also it should not break #34784 again and the time_zone should still not be saved in the visualizations saved object.

Checklist

Use strikethroughs to remove checklist items you don't feel are applicable to this PR.

• [ ] This was checked for cross-browser compatibility, including a check against IE11
• [ ] Any text added follows EUI's writing guidelines, uses sentence case text and includes i18n support
• [ ] Documentation was added for features that require explanation or tutorials
• Unit or functional tests were updated or added to match the most common scenarios
• [ ] This was checked for keyboard-only and screenreader accessibility

For maintainers

• [ ] This was checked for breaking API changes and was labeled appropriately
• [ ] This includes a feature addition or change that requires a release note and was labeled appropriately

[elasticmachine]

Pinging @elastic/kibana-app

[elasticmachine]

Pinging @elastic/kibana-app-arch

[elasticmachine]

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• continuous-integration/kibana-ci/pull-request

[flash1293]

Tested and works for me, timezones switch with the configured one on non-rollup vis, always use the rollup timezone for rollup vis.

The Save button being clickable even if nothing has changed seems to be a general thing, it might even be intentional, not sure if we even should "fix" this.

[timroes]

@flash1293 yeah I think that's actually desired behavior so far and we only want to block saving if the user is in a "touched but not applied" state. But as long as the state is valid we don't prevent them from saving. Actually it would also be the only way right now to use "Save as new visualization" even if you haven't made any changes.

[flash1293]

@timroes That's what I had in mind. There is probably some code which can be thrown away because of this, but definitely a low prio task which could be tackled during EUI-ification.

[ppisljar]

code lgtm

[lukeelmers]

Code LGTM too! Tested Chrome OSX and verified the issue appears to be fixed

[jen-huang]

Code LGTM and I tested locally with US/Hawaii timezone.

[elasticmachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request