Roll Skia from e79bb32365ea to 4ac9aadd306b (4 revisions)

https://skia.googlesource.com/skia.git/+log/e79bb32365ea..4ac9aadd306b

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 djsollen@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: I16b6a043b5a643ae213aa6390c88e28c07192c30