Account malloc mmaped pages as native heap.

Currently when malloc uses a page rather than brk the heap gets accounted as
ashmem memory. Previously the memory would be accounted as unknown but since
[1] it gets accounted as ashmem. This change makes the accounting see this
memory as being native, ie the same kind of memory we associate with brk.

[1] https://android-review.googlesource.com/#/c/49583/3

Change-Id: I6f496cfeb590268d41d8e047b12cd5c90359e2b0
Track stack memory in MemoryInfo.

In /proc/pid/maps the main stack is identified as "[stack]". In Linux 3.4
thread stacks are identified as "[stack:<tid>]" where <tid> is the thread ID of
the thread using that stack. Add support in MemInfo's otherStats to track
memory being used by the stack.

Add sanity check on the length of the otherStats array.
Add detail messages to two null pointer exceptions.

Bug: 8265251

Change-Id: I2b228b147da9bdc5c7a4d825dfc628fcc7923927
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
Enable vecorized bitmaps for all devices

Change-Id: I2231234adf115cf7f83c4b2778b53461f7a5587e