[atoms] Fix getText atom to capitalize Cyrillic text

The change to getText atom by commit c0f3e3c caused a regression in
ChromeDriver, and Cyrillic words are no longer capitalized properly
(see https://crbug.com/chromedriver/3421). The problem is \b doesn't
recognize Cyrillic word boundaries. This is fixed by combinine logic
before and after commit c0f3e3c.

Signed-off-by: Alexei Barantsev <barancev@gmail.com>