Roll external/skia d1537036a..83de8a6f8 (1 commits)

https://skia.googlesource.com/skia.git/+log/d1537036a..83de8a6f8

2019-01-15 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/angle2 f3179a6a1763..d3e0e84ce7e1 (1 commits)

The AutoRoll server is located here: https://autoroll-internal.skia.org/r/android-master-autoroll

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

If the roll is causing failures, please contact the current sheriff, who should
be CC'd on the roll, and stop the roller if necessary.

Test: Presubmit checks will test this change.
Change-Id: I435166a8652ee6d811abc0433b345759686610e8
Exempt-From-Owner-Approval: The autoroll bot does not require owner approval.