This is the first step in a three part change:
(1) Skia: Add SkBRDAllocator.
(2) Android: Make JavaPixelAllocator and RecyclingClippingPixelAllocator
implement SkBRDAllocator.
(3) Skia: Change SkBitmapRegionDecoder to use SkBRDAllocator and take
advantage of zero allocated memory when possible.
BUG=skia:
Review URL: https://codereview.chromium.org/1423253004
Rename SkCodecTools.h to SkBitmapRegionDecoderPriv.h
Move BRD code to its own directory in tools. This
allows us to not need to expose the entire tools
directory in Android.
BUG=skia:
Review URL: https://codereview.chromium.org/1417393004