Make work challenge pattern resizeable.

Currently in split-screen mode if work challenge window is made too narrow,
the dots of the pattern will go beyond window/screen boundaries. This change
makes pattern behave in the same way as primary profile pattern does, see
confirm_lock_pattern_normal.xml

Fixes: 133135598
Test: manual, resizing work challenge in portrait and landscape.
Change-Id: I40649911c2b7c587bf0b7e4a5c0449a5c2b7abb0