SKIA: import Blend and Opaque optimizations from CAF Chromium

This is a squash of 2 other commits:

 SWE: Skia Neon functions

Assembly optimized 3 blitting related functions:
S32A_D565_Opaque
S32A_Opaque_BlitRow32
S32A_Blend_BlitRow32

* S32A_D565_Opaque:
  Use neon instructions to optimize BLIT routine which operates on
  32-bit source ARGB pixel and 16-bit destination RGB pixel. Here,
  we process 16-pixels in an iteration. We use regular (32-bit)
  arm instructions when number of pixels is less than 16 or the
  architecture doesn't support SIMD/NEON instructions.

* S32A_Opaque_BlitRow32:
  Use neon instructions to optimize BlitRow32

* S32A_Blend_BlitRow32:
  Optimize S32A_Blend_BlitRow32 using neon instructions for armv7
  based targets and using regular arm instructions for armv6 based
  targets.

Change-Id: I7dfcf1b3bacbc4546ec4c0bf13f5d4949036aaa8

SWE: Add calls into neon functions

Change-Id: I7a02b0734cdd7609c5afe1735bdb184adbd2d7ac