Summary:
Fixes https://github.com/facebook/react-native/issues/27137
This PR fixes an issue on iOS where RCTTextView height is not calculated as it should for some fonts where font `leading` attributed is not equal to zero, which results in wrong baseline alignment behaviour.
The fix for this is by setting `usesFontLeading` property of `NSLayoutManager` to `NO`, which results is a layout behavior that is similar to `UILabel`
Probably the documentation for `usesFontLeading` describes why UILabel has a different (correct) layout behavior in that case
> // By default, a layout manager will use leading as specified by the font. However, this is not appropriate for most UI text, for which a fixed leading is usually specified by UI layout guidelines. These methods allow the use of the font's leading to be turned off.
## Changelog
[iOS] [Fixed] - Fix RCTTextView layout issue that happens on some font with `leading` attribute not equal to zero, which causes wrong base-alignment layout
Pull Request resolved: https://github.com/facebook/react-native/pull/27195
Test Plan:
Below are the test results before and after the change, and comparing that to native UILabel behavior.
The test is done with using system font and custom font (`GothamNarrow-Medium`) and font size 50
[GothamNarrow-Medium.otf.zip](https://github.com/facebook/react-native/files/3832143/GothamNarrow-Medium.otf.zip)
```js
const App: () => React$Node = () => {
return (
<View style={{flex: 1, margin: 40, flexDirection: 'row', justifyContent: 'center', alignItems: 'baseline'}}>
<View style={{width: 30, height: 30, backgroundColor: 'lightgray'}} />
<Text style={{fontSize: 50, backgroundColor: 'green', fontFamily: 'GothamNarrow-Medium'}}>{'Settings'}</Text>
</View>
);
};
```
-------
### Before the fix
<img width="962" alt="Screenshot 2019-11-11 at 16 53 26" src="https://user-images.githubusercontent.com/5355138/68601049-dd778780-04a3-11ea-879e-cc7b4eb2af95.png">
-----
### After the fix
<img width="944" alt="Screenshot 2019-11-11 at 16 55 11" src="https://user-images.githubusercontent.com/5355138/68601180-1d3e6f00-04a4-11ea-87bc-61c6fa2cdb18.png">
-----
### Using `UILabel`
<img width="805" alt="Screenshot 2019-11-11 at 16 59 28" src="https://user-images.githubusercontent.com/5355138/68601487-b2d9fe80-04a4-11ea-9a0f-c025c7753c24.png">
Differential Revision: D19576556
Pulled By: shergin
fbshipit-source-id: 4eaafdab963c3f53c461884c581e205e6426718a
5d08aab526
