Roll src/third_party/skia/ f6f7b67ac..50d4a6a66 (9 commits)

https://skia.googlesource.com/skia.git/+log/f6f7b67ac230..50d4a6a66190

$ git log f6f7b67ac..50d4a6a66 --date=short --no-merges --format='%ad %ae %s'
2018-02-16 skcms-skia-autoroll Roll skia/third_party/externals/skcms/ c42baa572..0fb1530a0 (1 commit)
2018-02-16 bsalomon Fix nullptr access when ProcessorOptimizationValidationTest fails
2018-02-16 herb Add a generalized array of bytes with a given alignment
2018-02-16 jvanverth Add an actual config for GPU NativeFonts tests
2018-02-15 mtklein register SIGTERM handler in DM
2018-02-15 caryclark improve bookmaker defines and references
2018-02-15 brianosman Fix flicker when changing backend on iOS viewer
2018-02-15 fmalita Generic "directory" viewer slide
2018-02-15 brianosman Avoid creating MIPs until necessary when MIP bias is active

Created with:
  roll-dep src/third_party/skia


The AutoRoll server is located here: https://autoroll.skia.org

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.


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
TBR=caryclark@chromium.org

Change-Id: Iae44bed11eac4789d4da0d99368ad2ffc808b56f
Reviewed-on: https://chromium-review.googlesource.com/924264
Commit-Queue: skia-chromium-autoroll <skia-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Reviewed-by: skia-chromium-autoroll <skia-chromium-autoroll@skia-buildbots.google.com.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/master@{#537366}

DEPS

@@ -79,7 +79,7 @@ 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': 'f6f7b67ac230b14a725fbdabe951c70ea5b4428f',
+  'skia_revision': '50d4a6a661909a36d259e3c6007337af8050a9fe',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.