Fix textAttributes not applied when typing text (#23585)

Summary:
Currently, if we has `defaultValue`, textAttributes like `letterSpacing` can works, but if textinput has not default text, when we typing the text, some attributes not applied.

[iOS] [Fixed] - Fix textAttributes not applied when typing text
Pull Request resolved: https://github.com/facebook/react-native/pull/23585

Differential Revision: D14206568

Pulled By: cpojer

fbshipit-source-id: 7db276d811684bf6e01f8d30287cca80095db87c

Libraries/Text/TextInput/Multiline/RCTUITextView.m

@@ -11,6 +11,7 @@
 #import <React/UIView+React.h>
 
 #import "RCTBackedTextInputDelegateAdapter.h"
+#import "RCTTextAttributes.h"
 
 @implementation RCTUITextView
 {
@@ -19,6 +20,8 @@
   RCTBackedTextViewDelegateAdapter *_textInputDelegateAdapter;
 }
 
+@synthesize reactTextAttributes = _reactTextAttributes;
+
 static UIFont *defaultPlaceholderFont()
 {
   return [UIFont systemFontOfSize:17];
@@ -88,6 +91,20 @@ static UIColor *defaultPlaceholderColor()
   _placeholderView.textColor = _placeholderColor ?: defaultPlaceholderColor();
 }
 
+- (void)setReactTextAttributes:(RCTTextAttributes *)reactTextAttributes
+{
+  if ([reactTextAttributes isEqual:_reactTextAttributes]) {
+    return;
+  }
+  self.typingAttributes = reactTextAttributes.effectiveTextAttributes;
+  _reactTextAttributes = reactTextAttributes;
+}
+
+- (RCTTextAttributes *)reactTextAttributes
+{
+  return _reactTextAttributes;
+}
+
 - (void)textDidChange
 {
   _textWasPasted = NO;