[SimpleFormIterator] add TransitionProps prop

[cherniavskii]

This PR adds ability to override CSSTransition props.

Together with #3223 adds ability to workaround #3220 in user land:

<ArrayInput source="backlinks">
-  <SimpleFormIterator>
+  <SimpleFormIterator TransitionProps={{ timeout: 400 }}>
    <RichTextInput source="url" />
  </SimpleFormIterator>
</ArrayInput>

May be worth to decrease default timeout in the future, but adding ability for workaround is a good first step.

[djhi]

Thanks! As this is a new feature, can you target the next branch?

[djhi]

Can you rename it to transitionProps?

[cherniavskii]

I used material-ui naming pattern here - see ExpansionPanel TransitionProps - https://material-ui.com/api/expansion-panel/#props

Maybe it's worth to stick with it?

[cherniavskii]

From component's API perspective, it's indeed a new feature.
From the other hand, it's the only way to solve #3220 in user land, which is present on current master.

I'll change target branch to next, but could you please consider cherrypicking it to master branch, so users will have a workaround before react-admin 3.0 release? This change is backwards compatible.

[djhi]

Ok, can you wait for @fzaninotto review then before switching branch ?

[cherniavskii]

@djhi sure

[fzaninotto]

It's indeed a new feature, please PR against next rather than master. The 2.x branch is feature-freeze.

[djhi]

Any news on this one?

[djhi]

Thanks!