Roll Skia from a4bb06463012 to a70445f40898 (3 revisions)

https://skia.googlesource.com/skia.git/+log/a4bb06463012..a70445f40898

If this roll has caused a breakage, revert this CL and stop the roller
using the controls here:
https://skia-autoroll.corp.goog/r/android-master-autoroll
Please CC scroggo@google.com on the revert to ensure that a human
is aware of the problem.

To report a problem with the AutoRoller itself, please file a bug:
https://bugs.chromium.org/p/skia/issues/entry?template=Autoroller+Bug

Documentation for the AutoRoller is here:
https://skia.googlesource.com/buildbot/+doc/master/autoroll/README.md

Test: Presubmit checks will test this change.
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Change-Id: Icba637612d484eec79de7293ae65c9dfaf79187a