Roll external/skia 81b7e3df3..346f82c1c (17 commits)

https://skia.googlesource.com/skia.git/+log/81b7e3df3..346f82c1c

2019-06-04 mtklein@google.com print 1/K floats as fractions
2019-06-04 mtklein@google.com move peepholes where they're relevant
2019-06-04 fmalita@chromium.org [skottie] Initial text range selector support
2019-06-04 mtklein@google.com print SKVM test failures
2019-06-04 mtklein@google.com allow two immediates
2019-06-04 robertphillips@google.com Make color initialization version of createBackendTexture public
2019-06-04 mtklein@google.com add SkVMBuilders.* to DM deps in G3
2019-06-04 michaelludwig@google.com Extract GrQuadList into separate header
2019-06-04 borenet@google.com [infra] Fixes for chrome_release_branch
2019-06-04 mtklein@google.com dump register and instruction count
2019-06-04 mtklein@google.com add extract instruction
2019-06-04 mtklein@google.com add pack instruction
2019-06-04 recipe-mega-autoroller@chops-service-accounts.iam.gserviceaccount.com Roll recipe dependencies (trivial).
2019-06-04 mtklein@google.com add mul_unorm8 instruction
2019-06-04 mtklein@google.com centralize test/bench SkVM builders
2019-06-04 skia-autoroll@skia-public.iam.gserviceaccount.com Roll skia/third_party/skcms ca5b4470be98..386ae89d2b64 (1 commits)
2019-06-04 robertphillips@google.com Switch all internel uses of GrContext::createBackendTexture over to initialized versions

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: I6938f1ea2314d732efc22076e5b4a889dd17650e
Exempt-From-Owner-Approval: The autoroll bot does not require owner approval.