Roll src/third_party/skia b7b2da871e95..255569187f27 (23 commits) (#8002)

https://skia.googlesource.com/skia.git/%2Blog/b7b2da871e95..255569187f27

git log b7b2da871e959ce9d412498b0378f5ace0dd5808..255569187f27d854a78ce67a62713fadc2d5e292 --date=short --no-merges --format=%ad %ae %s
2019-03-01 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/angle2 5de69e91bd93..5546fb4fdd85 (4 commits)
2019-02-27 csmartdalton@google.com Make GrMesh compatible with instanced draws that have no attribs
2019-02-28 reed@google.com Move responsibility to onMakeContext for device colorspace decision
2019-02-28 kjlubick@google.com [canvaskit] Add support for external fonts
2019-02-26 csmartdalton@google.com Revert "Drop unused shader support for sample variables"
2019-02-28 brianosman@google.com Particles: Removed emitters, added more full-featured position affectors
2019-02-28 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader c6eb41bebc27..a1924739029e (2 commits)
2019-02-28 recipe-roller@chromium.org Roll recipe dependencies (trivial).
2019-02-28 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader bc63cf9c511b..c6eb41bebc27 (3 commits)
2019-02-28 jvanverth@google.com Fix a couple of Mac windowing issues.
2019-02-28 bsalomon@google.com Remove support for SkDeferredDisplayListRecorder::DelayReleaseCallback::kNo.
2019-02-28 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/swiftshader 201f136c9907..bc63cf9c511b (1 commits)
2019-02-28 thakis@chromium.org skia: Fix -Wextra-semi warnings in non-dcheck builds.
2019-02-27 michaelludwig@google.com Reland "Add general quad API to SkGpuDevice"
2019-02-28 brianosman@google.com Fix scaling error in SkLights::makeColorSpace
2019-02-28 skia-autoroll@skia-public.iam.gserviceaccount.com Roll ../src 61d99852c465..1dc32aecaa61 (2053 commits)
2019-02-28 benjaminwagner@google.com Remove OS condition from isolate files
2019-02-28 kjlubick@google.com [canvaskit][pathkit] Remove flaky/low-utility Debug tests
2019-02-28 skia-autoroll@skia-public.iam.gserviceaccount.com Roll third_party/externals/angle2 4b314eefc839..5de69e91bd93 (1 commits)
2019-02-28 fmalita@chromium.org solink with --start-group/--end-group
2019-02-27 scroggo@google.com Enable Skia for Windows
2019-02-28 halcanary@google.com SkQP Documentation
2019-02-28 kjlubick@google.com [canvaskit] Support image assets for Skottie

The AutoRoll server is located here: https://autoroll.skia.org/r/skia-flutter-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 (scroggo@google.com), and stop
the roller if necessary.

DEPS

@@ -23,7 +23,7 @@ vars = {
   'fuchsia_git': 'https://fuchsia.googlesource.com',
   'github_git': 'https://github.com',
   'skia_git': 'https://skia.googlesource.com',
-  'skia_revision': 'b7b2da871e959ce9d412498b0378f5ace0dd5808',
+  'skia_revision': '255569187f27d854a78ce67a62713fadc2d5e292',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

ci/licenses_golden/licenses_skia

-Signature: f25dc20a23aafd38437994dfd80cdd57
+Signature: 84d0579ee895fb12763c036a74644ea9
 
 UNUSED LICENSES:
 
@@ -2133,8 +2133,11 @@ FILE: ../../../third_party/skia/experimental/canvaskit/perf/assets/confetti.json
 FILE: ../../../third_party/skia/experimental/canvaskit/perf/assets/drinks.json
 FILE: ../../../third_party/skia/experimental/canvaskit/perf/assets/lego_loader.json
 FILE: ../../../third_party/skia/experimental/canvaskit/perf/assets/onboarding.json
+FILE: ../../../third_party/skia/experimental/canvaskit/postamble.js
+FILE: ../../../third_party/skia/experimental/canvaskit/preamble.js
 FILE: ../../../third_party/skia/experimental/canvaskit/ready.js
 FILE: ../../../third_party/skia/experimental/canvaskit/release.js
+FILE: ../../../third_party/skia/experimental/canvaskit/skottie.js
 FILE: ../../../third_party/skia/experimental/docs/animationCommon.js
 FILE: ../../../third_party/skia/experimental/docs/backend.js
 FILE: ../../../third_party/skia/experimental/docs/canvasBackend.js
@@ -2144,7 +2147,6 @@ FILE: ../../../third_party/skia/experimental/docs/jsonbaseddoc.htm
 FILE: ../../../third_party/skia/experimental/docs/svgBackend.js
 FILE: ../../../third_party/skia/experimental/docs/svgbaseddoc.htm
 FILE: ../../../third_party/skia/experimental/docs/utilities.js
-FILE: ../../../third_party/skia/infra/bots/android_bin.isolate
 FILE: ../../../third_party/skia/infra/bots/assets.isolate
 FILE: ../../../third_party/skia/infra/bots/assets/android_ndk_darwin/VERSION
 FILE: ../../../third_party/skia/infra/bots/assets/android_ndk_linux/VERSION
@@ -4693,14 +4695,12 @@ FILE: ../../../third_party/skia/modules/particles/include/SkParticleAffector.h
 FILE: ../../../third_party/skia/modules/particles/include/SkParticleData.h
 FILE: ../../../third_party/skia/modules/particles/include/SkParticleDrawable.h
 FILE: ../../../third_party/skia/modules/particles/include/SkParticleEffect.h
-FILE: ../../../third_party/skia/modules/particles/include/SkParticleEmitter.h
 FILE: ../../../third_party/skia/modules/particles/include/SkParticleSerialization.h
 FILE: ../../../third_party/skia/modules/particles/include/SkReflected.h
 FILE: ../../../third_party/skia/modules/particles/src/SkCurve.cpp
 FILE: ../../../third_party/skia/modules/particles/src/SkParticleAffector.cpp
 FILE: ../../../third_party/skia/modules/particles/src/SkParticleDrawable.cpp
 FILE: ../../../third_party/skia/modules/particles/src/SkParticleEffect.cpp
-FILE: ../../../third_party/skia/modules/particles/src/SkParticleEmitter.cpp
 FILE: ../../../third_party/skia/modules/particles/src/SkReflected.cpp
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