Exception when saving a new view with start date or end date filters

When I try to save a new view (not an existing view), it works fine until I add either the start date or the end date filter. This is somewhat similar to #2850463: Fix Error whenever saving either of the provided google_analytics_reports view without any customization except that in that issue, the "fix" was made only for the views provided by the module. In fact, there was a patch in #8 (also in #24) comment that could have worked but didn't for some reason.

Tracing back in how views defines its schema, I think that we really should define the schema for the filter plugin types.

Steps to reproduce:

1. Install and authenticate the module.
2. Add a new view with Google Analytics as source.
3. Add any fields you want.
4. Save the view, it should work fine.
5. Now, edit the view and add the start date and/or end date filter. Set offset type and specify any offset.
6. The preview should work.
7. Save, and it will throw an exception.