TextInput controlled selection broken on both ios and android.

This issue is a continuation of the discussion:
https://github.com/facebook/react-native/commit/dff490d140010913d3209a2f3e987914b9c4eee4#commitcomment-39332764
The link to the sample project that demonstrates the issues:
https://github.com/Ginger-Labs/Input-bug

Description

Controlled selection seems to be broken on both ios and android, to demonstrate the issues I created a sample project (find the link above).

React Native version:

System:
OS: macOS 10.15.4
CPU: (8) x64 Intel(R) Core(TM) i7-7820HQ CPU @ 2.90GHz
Memory: 1.55 GB / 16.00 GB
Shell: 5.7.1 - /bin/zsh
Binaries:
Node: 10.14.2 - /usr/local/bin/node
Yarn: 1.13.0 - /usr/local/bin/yarn
npm: 6.14.5 - ~/.npm-global/bin/npm
Watchman: 4.9.0 - /usr/local/bin/watchman
SDKs:
iOS SDK:
Platforms: iOS 13.5, DriverKit 19.0, macOS 10.15, tvOS 13.4, watchOS 6.2
Android SDK:
API Levels: 23, 24, 25, 26, 27, 28, 29
Build Tools: 26.0.3, 28.0.3, 29.0.0, 30.0.0
System Images: android-28 | Google APIs Intel x86 Atom, android-28 | Google Play Intel x86 Atom, android-29 | Google APIs Intel x86 Atom, android-29 | Google Play Intel x86 Atom_64
Android NDK: 21.1.6352462
IDEs:
Android Studio: 3.6 AI-192.7142.36.36.6392135
Xcode: 11.5/11E608c - /usr/bin/xcodebuild
npmPackages:
react: ~16.9.0 => 16.9.0
react-native: ~0.62.2 => 0.62.2
npmGlobalPackages:
create-react-native-app: 3.4.0
react-native-app-id: 0.0.5
react-native-cli: 2.0.1

Steps To Reproduce

The reproduction steps are in the sample project's ReadMe file.
For simplicity purposes, I will post them here as well:

SIM - iPhone 11 (13.4.1):

1. Click on the "Click Me" Button, set the cursor in the middle, add some text, click on the button again: Notice the text is set to needed one but the selection is not 10
2. Input text: "Hello world", move cursor in between words, click on "@":
   Expected: "Hello @Mihailworld" with the cursor at 13
   Actual: "Hello @Mihailworld" with the cursor at the end of the whole string.

SIM - nexus 6P API28

1. Add text, click on enter (new line).
   Expected: The text stays and a new line is created with "-" in front.
   Actual: The first line becomes empty and the second line "-".
2. Press enter twice and you will get a:
   Exception in native call java.lang.IndexOutOfBoundsException: setSpan (6 ... 6) ends beyond length 3
3. Press "@" twice and observe the same bug above.

Expected Results

I expect the TextInput to work as intended (unless I am missing something conceptual).

Snack, code example, screenshot, or link to a repository:

https://github.com/Ginger-Labs/Input-bug

Bắt đầu với các bước tái hiện trong README của dự án mẫu Input-bug được liên kết và tái hiện hành vi lựa chọn có kiểm soát của TextInput trên các môi trường iOS và Android được liệt kê. So sánh các kết quả quan sát được của con trỏ, ký tự xuống dòng và IndexOutOfBoundsException với các kết quả mong đợi; công việc hoàn tất khi lựa chọn có kiểm soát hoạt động chính xác trên cả hai nền tảng.