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Disable usesFontLeading for NSLayoutManager on iOS to fix baseline …
…alignment issue on some fonts (#27195)

Fixes #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: #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


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>

### Before the fix

<img width="962" alt="Screenshot 2019-11-11 at 16 53 26" src="">

### After the fix
<img width="944" alt="Screenshot 2019-11-11 at 16 55 11" src="">

### Using `UILabel`
<img width="805" alt="Screenshot 2019-11-11 at 16 59 28" src="">

Differential Revision: D19576556

Pulled By: shergin

fbshipit-source-id: 4eaafdab963c3f53c461884c581e205e6426718a
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ahmedibrahim-tomtom authored and facebook-github-bot committed Jan 27, 2020
1 parent 6237cfb commit 5d08aab526b2702b46ff75ea7e943a33aa6df288
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@@ -233,6 +233,7 @@ - (NSTextStorage *)textStorageAndLayoutManagerThatFitsSize:(CGSize)size
textContainer.maximumNumberOfLines = _maximumNumberOfLines;

NSLayoutManager *layoutManager = [NSLayoutManager new];
layoutManager.usesFontLeading = NO;
[layoutManager addTextContainer:textContainer];

NSTextStorage *textStorage =
@@ -97,6 +97,7 @@ - (void)drawAttributedString:(AttributedString)attributedString
textContainer.maximumNumberOfLines = paragraphAttributes.maximumNumberOfLines;

NSLayoutManager *layoutManager = [NSLayoutManager new];
layoutManager.usesFontLeading = NO;
[layoutManager addTextContainer:textContainer];

NSTextStorage *textStorage =

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