Roll src/third_party/skia/ c9a642edf..cb88470d8 (2 commits)

https://skia.googlesource.com/skia.git/+log/c9a642edf2d1..cb88470d82d6

$ git log c9a642edf..cb88470d8 --date=short --no-merges --format='%ad %ae %s'
2018-03-19 bsalomon Remove SkSurface::MakeFromBackendTextureAsRenderTarget variant that doesn't take SkColorType
2018-03-19 bsalomon Revert "New read pixels implementation that is simpler but does all conversions on CPU."

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;luci.chromium.try:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
TBR=jvanverth@chromium.org

Change-Id: Ie5d73a29c6be4c8b4d4a240e2a2c700401375f78
Reviewed-on: https://chromium-review.googlesource.com/969073
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@{#544145}

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': 'c9a642edf2d1c7f5380fe829adbb1a692f9969a6',
+  'skia_revision': 'cb88470d82d646972a7e83d04bb19444d87dd840',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling V8
   # and whatever else without interference from each other.