Fixes capitalized I's when emojiis are present after the text being e…

…dited. (#21951)

Summary:
Fixes #21243.
Fixes #20908.

Credit goes to superandrew213 who provided the patch based on 0.56; this commit merges and resolved the conflict introduced in 0.57.
Pull Request resolved: #21951

Differential Revision: D13980799

Pulled By: cpojer

fbshipit-source-id: 6b9f1a1ae54ad9dba043005d683d6a221472c729

Libraries/Text/TextInput/RCTBaseTextInputView.m

@@ -105,12 +105,22 @@ - (BOOL)textOf:(NSAttributedString*)newText equals:(NSAttributedString*)oldText{
   // Similarly, when the user is in the middle of inputting some text in Japanese/Chinese, there will be styling on the
   // text that we should disregard. See https://developer.apple.com/documentation/uikit/uitextinput/1614489-markedtextrange?language=objc
   // for more info.
+  // If the user added an emoji, the sytem adds a font attribute for the emoji and stores the original font in NSOriginalFont.
   // Lastly, when entering a password, etc., there will be additional styling on the field as the native text view
   // handles showing the last character for a split second.
+  __block BOOL fontHasBeenUpdatedBySystem = false;
+  [oldText enumerateAttribute:@"NSOriginalFont" inRange:NSMakeRange(0, oldText.length) options:0 usingBlock:^(id value, NSRange range, BOOL *stop) {
+    if (value){
+      fontHasBeenUpdatedBySystem = true;
+    }
+  }];
+
   BOOL shouldFallbackToBareTextComparison =
     [self.backedTextInputView.textInputMode.primaryLanguage isEqualToString:@"dictation"] ||
     self.backedTextInputView.markedTextRange ||
-    self.backedTextInputView.isSecureTextEntry;
+    self.backedTextInputView.isSecureTextEntry ||
+    fontHasBeenUpdatedBySystem;
+
   if (shouldFallbackToBareTextComparison) {
     return ([newText.string isEqualToString:oldText.string]);
   } else {