Rephrase the base text for accessibility large pointer icon.

L10N team requested that the text might not fit within the
CHAR_LIMIT=35 in some languages. Rather than increasing the limit,
I think it's better to simplify the original text so that
its translations are unlikely to break the limit of chars.

Bug: 26123263
Change-Id: If9b338d2f051c161a71e8b20c9526be2d10e0cc1