1. The way for computing the magnified region was simplistic and
incorrect. It was ignoring window layering resulting in broken
behavior. For example, if the IME is up, then the everything else
is magnifed and the IME not. Now the keyguard appears and covers
the IME but the magnified region does not expand while it would
since the keyguard completely covers the not magnified IME window.
bug:7138937
Change-Id: I21414635aefab700ce75d40f3e913c1472cba202