Eliminate setText call in applyNewStyles on Android

[tomekzaw]

Details

This PR refactors the implementation of applyNewStyles method on Android.

Currently, in applyNewStyles we obtain the current value using getText method and pass it to setText method in order to trigger MarkdownTextWatcher. This works fine but can lead to infinite loop because calling setText (or even setTextKeepState) generates a selection update event. In live-markdown example app, onSelectionChange callback always calls setSelection (without comparing start and end fields so it updates the reference to selection state) which results in render that leads to another applyNewStyles call (not sure how exactly, though).

Instead, we call applyMarkdownFormatting which doesn't emit selection change event.

Related Issues

Required by #607.

Manual Tests

Linked PRs