Roll Skia from fd9745eee98f to 3f479f3da7f8 (1 revision) (#18623)

https://dart.googlesource.com/external/github.com/flutter/engine/+/339e1607e78c69fd6452453c89dc1ba19fcbeeb2
diff --git a/commits.json b/commits.json
index fa39513..6488c9c 100644
--- a/commits.json
+++ b/commits.json
@@ -1,5 +1,5 @@
 {
-  "external/github.com/flutter/engine":"2b616caad05cb8102c04a0eeaf9984951162fffc",
+  "external/github.com/flutter/engine":"339e1607e78c69fd6452453c89dc1ba19fcbeeb2",
   "external/github.com/flutter/flutter":"5663e02645a6e69fedfe8553cbe7940cbb592be9",
   "sdk":"7a63d5889cb413584188f9a73eb88778d81d0ab3"
 }
\ No newline at end of file