Add SelectTextOnFocusBehavior to automatically select the content of a TextBox when it is focused. - #836

Tests: 100.0%. Drop of 421 cases in total count! 0 out of 39 cases failing (100.0% threshold)

Tracks: 0 new, 0 flaky, 0 consistent, 0 passing, 0 resolved

Duration: 34 seconds and 993.0 milliseconds