Add arm tail code.

CQ_INCLUDE_TRYBOTS=skia.primary:Test-Android-Clang-Nexus10-CPU-Exynos5250-arm-Release-Android

Change-Id: Ia0e9f32d0324e66c9d4812dbb156a2b858d49a13
Reviewed-on: https://skia-review.googlesource.com/18127
Commit-Queue: Herb Derby <herb@google.com>
Commit-Queue: Mike Klein <mtklein@chromium.org>
Reviewed-by: Mike Klein <mtklein@chromium.org>
5 files changed