Duplicateed letters fix

Author: safaiyeh

ReactAndroid/src/main/java/com/facebook/react/views/textinput/ReactEditText.java

@@ -503,7 +503,8 @@ public void maybeSetText(ReactTextUpdate reactTextUpdate) {
       // When we update text, we trigger onChangeText code that will
       // try to update state if the wrapper is available. Temporarily disable
       // to prevent an infinite loop.
-      getText().replace(0, length(), spannableStringBuilder);
+      getText().clear();
+      append(spannableStringBuilder);
     }
     mDisableTextDiffing = false;