FYI: JDK-8238535: Shape Clip does not work with AA rendering

[Alexey Ushakov]

Added check for previous op and call endEncoder if the op changes from AA to non AA (or vice versa)

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Commit messages:
 - JDK-8238535: Shape Clip does not work with AA rendering

Changes: https://git.openjdk.java.net/lanai/pull/9/files
 Webrev: https://webrevs.openjdk.java.net/lanai/9/webrev.00
  Issue: https://bugs.openjdk.java.net/browse/JDK-JDK-8238535
  Stats: 119 lines in 5 files changed: 85 ins; 21 del; 13 mod
  Patch: https://git.openjdk.java.net/lanai/pull/9.diff
  Fetch: git fetch https://git.openjdk.java.net/lanai pull/9/head:pull/9

PR: https://git.openjdk.java.net/lanai/pull/9