Bring back SkRasterPipeline::run() for one-off uses.

CQ_INCLUDE_TRYBOTS=skia.primary:Test-Ubuntu-GCC-GCE-CPU-AVX2-x86_64-Release-SKNX_NO_SIMD

Change-Id: I308b6d75f2987a667eead9a55760a2ff6aec2984
Reviewed-on: https://skia-review.googlesource.com/5353
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>
11 files changed