[DatePicker] Remove the dateAdapter prop

The dateAdapter prop is exposed as a sugar helper in order to allow this diff:

-<LocalizationProvider dateAdapter={x}>
-  <DatePicker />
-</LocalizationProvider>+
+<DatePicker dateAdapter={x} />

As far as I can envision the requirement of developers, I can only see a marginal use case for the prop:

• 70% of the cases, you are a developer, you want to get things down, you don’t have time to work on the tree-shaking of your application, you have a sprint to make progress on. You use LocalizationProvider at the root of your app.
• 30% of the cases, you have found time to dedicate on tree-shaking. You figure that you can solve the problem by creating a wrapper component for each date picker component. You create the wrapper, move the LocalizationProvider inside it, for instance:

import { DatePicker, DatePickerProps, LocalizationProvider } from '@material-ui/lab';
import dateAdapter from 'path-to-date-adapter';

const DatePicker = React.forwardRef(function DatePicker(props: DatePickerProps, ref: React.Ref<unknown>)) {
  return (
    <LocalizationProvider dateAdapter={dateAdapter}>
      <DatePicker ref={ref} {...props} />
    </LocalizationProvider>
  );
}

export default DatePicker;

Another advantage of dropping dateAdapter avoids having people ask what option they should use between the provider and the prop and also to prune the codebase of code that isn’t used frequently enough to justify the added complexity.

• I wonder if we should expose withDateAdapter as a public higher-order component? Probably not
• I wonder about making a poll to figure out what developers use. Happy to skip this part

[eps1lon]

I think that having x different ways to do things is to be encouraged if the x approaches come with different enough set of pros & cons and developers are interested in the different options.

Ok. I was not talking about this. I was talking about doing one thing. Not doing two things.

[eps1lon]

Same argument as always: Provide one API to do one thing not two. Glad you’re following here but I would hope you apply it everywhere.