LouiseHsu 9e79a79066 Add Look Up to iOS selection controls (flutter/engine#43308)
In native iOS, when Look Up is initiated on highlighted text, a view DDParsecCollectionViewController is presented with definitions of the the selected text if available, as well as Siri integrated suggestions. However, since the view controller is gated behind a private API, we will use [UIReferenceLibraryViewController](https://developer.apple.com/documentation/uikit/uireferencelibraryviewcontroller) instead, which is functionally identical and visually very similar.

| Native | UIReferenceLibraryViewController|
| ------------- | ------------- |
| <img src="https://github.com/flutter/engine/assets/36148254/763004f0-970f-4d8a-9a9a-133401ef0c1b" width="360" />| <img src="https://github.com/flutter/engine/assets/36148254/b20fe03f-6c9d-4a4a-98dc-8bcd840406db" width="360" />|

This PR is the engine portion of the changes that will allow this feature change.
This PR addresses https://github.com/flutter/flutter/issues/82907
More details are available in this [design doc](flutter.dev/go/add-missing-features-to-selection-controls)
2023-07-06 19:38:48 +00:00
..