RFR: 8242920: Gradient Paint doesn't work with metal

[Alexey Ushakov]

Implemented cyclic option for gradient paint

-------------

Commit messages:
 - 8242920: Gradient Paint doesn't work with metal

Changes: https://git.openjdk.java.net/lanai/pull/82/files
 Webrev: https://webrevs.openjdk.java.net/lanai/82/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8242920
  Stats: 25 lines in 3 files changed: 22 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/lanai/pull/82.diff
  Fetch: git fetch https://git.openjdk.java.net/lanai pull/82/head:pull/82

PR: https://git.openjdk.java.net/lanai/pull/82