Roll external/skia 932968904..8264b310d (3 commits)

https://skia.googlesource.com/skia.git/+log/932968904..8264b310d

2018-03-29 metzman@chromium.org Add libFuzzer style fuzzer for NullGLCanvas for use on OSS-Fuzz.
2018-03-29 robertphillips@google.com Fix up .fp files
2018-03-29 csmartdalton@google.com vulkan: Blacklist MSAA path renderer on Qualcomm drivers

The AutoRoll server is located here: https://android-roll.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.

Test: Presubmit checks will test this change.
Change-Id: I50fb823f67a3b634e0ab1a072aee21fab2b1e450
Exempt-From-Owner-Approval: The autoroll bot does not require owner approval.