Add beta preferences icons for Hebrew and Arabic

This patch reverses the beta preference icon, similarly to what
is done in other Beta features. However, because the image here
includes a letter, it needs to be adapted to other alphabets
and not just reversed, as it doesn't make sense to write an A
in the beginning of a Hebrew or an Arabic text.

This patch adds images for Arabic and Hebrew alphabets. The code
for picking the image is simple. If there's demand for more alphabets,
it can be made smarter.

Change-Id: I8a85689b8daa2ed805044925267cfeed956d3471
Merge "Add beta preferences icons for Hebrew and Arabic"