Temporary fix for buffer overrun issue.

Allocating the bitmap using getSafeSize() causes problems since
getSafeSize64() < getSize() if there is a stride. Since everywhere
else uses getSize() it results in a lot of possible buffer overruns.
The fix reverts to using getSize instead of getSafeSize64.

Bug: 15089814
Change-Id: Ia471cf9715672d57bb7eb61bf735064aeb405ffe