Roll src/third_party/skia/ ce8ea4c55..276e63361 (2 commits).

      https://chromium.googlesource.com/skia.git/+log/ce8ea4c55b6e..276e63361c73

$ git log ce8ea4c55..276e63361 --date=short --no-merges --format='%ad %ae %s'
2016-05-31 mbarbella Check results from calls to SkCubicClipper::ChopMonoAtY.
2016-05-31 scroggo Revert of Make SkPngCodec decode progressively. (patchset #18 id:340001 of https://codereview.chromium.org/1997703003/ )

BUG=613918

CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel
TBR=herb@google.com

Review-Url: https://codereview.chromium.org/2026993002
Cr-Commit-Position: refs/heads/master@{#397005}