ARM Skia NEON patches - 20 - New improved BitmapProcState code

ARM Skia NEON patches - 20 - New improved BitmapProcState code

BitmapProcState: new factorised code

This one basically factorises the clamp and repeat transformations with
some performance improvements. It has the benefit of being faster, much
easier to maintain (nearly three times less code for more work
done :-)), and more complete (all persp transformations weren't optimised
in the previous version).

It also introduces the use of can_truncate_to_fixed_for_decal where
useful.

The effect on benchmarks ranges from a 5% penalty to a 25% gain on a
Cortex-A9 and from a 5% penalty to a 100% gain on a Cortex-A15.

Signed-off-by: Kévin PETIT <kevin.petit@arm.com>
BUG=
R=djsollen@google.com, mtklein@google.com, luisjoseromeroesclusa@hotmail.com, reed@google.com

Author: kevin.petit.arm@gmail.com

Review URL: https://codereview.chromium.org/23835006

git-svn-id: http://skia.googlecode.com/svn/trunk@13218 2bbb7eff-a529-9590-31e7-b0007b416f81