RFR: 8285867 : Convert applet manual tests SelectionVisible.java to Frame and automate

[lawrence.andrews]

1) Removed Applet dependent code and used Frame as top level.
2) Automated the manual test.

@shurymury

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Commit messages:
 - 8285867 : Convert applet manual tests SelectionVisible.java to Frame and automate

Changes: https://git.openjdk.java.net/jdk/pull/8477/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8477&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8285867
  Stats: 212 lines in 4 files changed: 71 ins; 116 del; 25 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8477.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8477/head:pull/8477

PR: https://git.openjdk.java.net/jdk/pull/8477