Roll external/skia c0747bb21..31972f889 (2 commits)
Roll external/skia c0747bb21..31972f889 (2 commits)

https://skia.googlesource.com/skia.git/+log/c0747bb21..31972f889

2019-01-17 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader af4ed53dab6b..296aa2513448 (1 commits)
2019-01-17 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/angle2 dd34b3b9b707..d46165e3db5a (9 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: I35814cfffc121f20fedad7506d2d051e4c31a1ad
Exempt-From-Owner-Approval: The autoroll bot does not require owner approval.

aosp-mirror/platform_external_skia,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,Hikari-no-Tenshi/android_external_skia,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,Hikari-no-Tenshi/android_external_skia,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,Hikari-no-Tenshi/android_external_skia,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia,Hikari-no-Tenshi/android_external_skia,aosp-mirror/platform_external_skia,aosp-mirror/platform_external_skia