Roll Skia from a6ca0b135453 to 7724291b6e05 (8 revisions)

https://skia.googlesource.com/skia.git/+log/a6ca0b135453..7724291b6e05

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: I36c7309629eb83236a2c8adb54833638d68f2fb2