Roll src/third_party/skia 8966b55644c2..3b7e65107f67 (3 commits) (#7361)

https://skia.googlesource.com/skia.git/%2Blog/8966b55644c2..3b7e65107f67

git log 8966b55644c2623a199814fbe75a5130f373f1ff..3b7e65107f671e35674ab8bfc163d998039b81bf --date=short --no-merges --format=%ad %ae %s
2019-01-03 reed@google.com rm legacy FontMetrics from docs
2019-01-03 reed@google.com remove legacy fontmetrics flag
2019-01-03 reed@google.com rm unneeded encoding param

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

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 (bungeman@google.com), and stop
the roller if necessary.

DEPS

@@ -23,7 +23,7 @@ vars = {
   'fuchsia_git': 'https://fuchsia.googlesource.com',
   'github_git': 'https://github.com',
   'skia_git': 'https://skia.googlesource.com',
-  'skia_revision': '8966b55644c2623a199814fbe75a5130f373f1ff',
+  'skia_revision': '3b7e65107f671e35674ab8bfc163d998039b81bf',
 
   # When updating the Dart revision, ensure that all entries that are
   # dependencies of Dart are also updated to match the entries in the

ci/licenses_golden/licenses_skia

-Signature: 33f920184ef848545edc093632711eca
+Signature: c815a9fdad786a19310d2e8659e464bf
 
 UNUSED LICENSES: