Roll src/third_party/skia/ 6566b97b7..7947193c3 (4 commits)

https://skia.googlesource.com/skia.git/+log/6566b97b76d3..7947193c319b

$ git log 6566b97b7..7947193c3 --date=short --no-merges --format='%ad %ae %s'
2017-10-27 csmartdalton Merge clip rects in GrReducedClip
2017-10-27 angle-deps-roller Roll skia/third_party/externals/angle2/ 4ddae3598..aa9c396b7 (2 commits)
2017-10-26 bsalomon Remove fallback to path drawing from stencil and cover text context.
2017-10-27 angle-deps-roller Roll skia/third_party/externals/angle2/ 9cd7163e1..4ddae3598 (1 commit)

Created with:
  roll-dep src/third_party/skia


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

If the roll is causing failures, see:
http://www.chromium.org/developers/tree-sheriffs/sheriff-details-chromium#TOC-Failures-due-to-DEPS-rolls


CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel;master.tryserver.chromium.android:android_optional_gpu_tests_rel
TBR=mtklein@chromium.org

Change-Id: Ic9e3c2ca609bda45d32dceea048b95837a64d169
Reviewed-on: https://chromium-review.googlesource.com/742189Reviewed-by: Skia Deps Roller <skia-deps-roller@chromium.org>
Commit-Queue: Skia Deps Roller <skia-deps-roller@chromium.org>
Cr-Commit-Position: refs/heads/master@{#512327}

DEPS

@@ -55,7 +55,7 @@ vars = {
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and whatever else without interference from each other.
-  'skia_revision': '6566b97b76d3cb76ee255a3d128d048376d300bd',
+  'skia_revision': '7947193c319bced2ef557971550e196adbe60966',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.