PIE: support for expandable notifications

Change-Id: I47721bf8693b5fde008c01cfc70201c43a80ae18
frameworks/base: vectorize Bitmap operations

Enable gcc vectorizing optimizations for Bitmap operations within
libandroid_runtime.so.  Adds -ftree-vectorize -mvectorize-with-neon-quad
-fprefetch-loop-arrays to functions and compiles Bitmap.cpp in ARM mode
(necessary to enable vectorizing optimizations) for appropriate targets.

Change-Id: I12defef6f47adf41af849df6e750097f5906d92d