Roll src/third_party/skia 30b83d4:3a9c903

Summary of changes available at:
https://chromium.googlesource.com/skia/+log/30b83d4..3a9c903

CQ_EXTRA_TRYBOTS=tryserver.blink:linux_blink_rel,linux_blink_dbg
TBR=hcm@google.com

Review URL: https://codereview.chromium.org/679053002

Cr-Commit-Position: refs/heads/master@{#301349}

DEPS

@@ -44,7 +44,7 @@ vars = {
   'boringssl_git': 'https://boringssl.googlesource.com',
   'libvpx_revision': '2e5ced5fd62a73f4f5687ab19520b3aad1c53f6f',
   'sfntly_revision': '1bdaae8fc788a5ac8936d68bf24f37d977a13dac',
-  'skia_revision': '30b83d45a3af444e6868c638d86442c2ea3e20c6',
+  'skia_revision': '3a9c903cde6102c194a2d58edb87398ab51e9d53',
   # Three lines of non-changing comments so that
   # the commit queue can handle CLs rolling Skia
   # and V8 without interference from each other.