Fix move selected text on iOS

[etoledom]

fixes #843
Maybe this one too: wordpress-mobile/WordPress-iOS#11583

This PR fixes an issue where the editor enters on a onFocus/onBlur infinite loop. This was easily reproduced by selecting text on a paragraph block, and moving it inside the same block.

I tracked the issue until this line:

gutenberg-mobile/react-native-aztec/src/AztecView.js

Line 149 in 6513ba8

this._onPress(event);

But we need it in order to let Gutenberg know that the TextView was focused by iOS. Needed to solve this issue: #702

With some investigation I noticed that textViewDidBeginEditing was sending one extra onFocus event that is not needed, and that triggered the loop. It was solved by sending the onFocus from becomeFirstResponder, with the proper checks.

To test:

• Run the example project on iOS
• Select a long paragraph block.
• Select some text long enough.
• Long press to move it and release it somewhere else in the block.
• Check that the editor behaves as expected.
• Check that the Hide Keyboard button stays functional after presenting the Links UI. (check for Dismissing Links UI (BottomSheet) disables hide keyboard button. #702 )
• Smoke test on Android.

[SergioEstevao]

Tested it on iOS and it's working great!

[etoledom]

Thank you @SergioEstevao !

@mkevins or @marecar3 would you mind smoke-testing this on Android? 🙏

The change on AztecView.js remove some (supposedly unnecessary) calls to onFocus.
Checking that onFocus is called when it's necessary on RichText should be enough (that the RichText based blocks are being focused properly on different scenarios).

[daniloercoli]

Tested on Android and worked as expected!

[etoledom]

Thank you!