Roll external/skia 086d80bcf..836ff5e40 (11 commits)

https://skia.googlesource.com/skia.git/+log/086d80bcf..836ff5e40

2019-04-30 fmalita@chromium.org [skottie] Mask feather support
2019-04-30 bungeman@google.com Use linear metrics with new FreeType light autohint.
2019-04-30 robertphillips@google.com Suppress the savelayer_clipmask test on some Android devices
2019-04-30 skia-recreate-skps@skia-swarming-bots.iam.gserviceaccount.com Update go_deps asset
2019-04-30 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ../src 2f6bc7b3cacb..b40205fdcd0e (330 commits)
2019-04-30 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader 28f142f1b0a2..6a12e092091c (8 commits)
2019-04-30 recipe-mega-autoroller@chops-service-accounts.iam.gserviceaccount.com Roll recipe dependencies (trivial).
2019-04-29 recipe-mega-autoroller@chops-service-accounts.iam.gserviceaccount.com Roll recipe dependencies (trivial).
2019-04-29 csmartdalton@google.com Reland "ccpr: Set atlas proxy size to draw bounds rather than backing size"
2019-04-29 recipe-mega-autoroller@chops-service-accounts.iam.gserviceaccount.com Roll recipe dependencies (trivial).
2019-04-29 recipe-mega-autoroller@chops-service-accounts.iam.gserviceaccount.com Roll recipe dependencies (trivial).

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Test: Presubmit checks will test this change.
Change-Id: I452813df7b5545399dd757d1ba52c726cc83637e
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