RFR: 8283701: Add final or sealed modifier to appropriate java.awt.color ICC_Profile API classes

[Phil Race]

This PR is similar to https://git.openjdk.java.net/jdk/pull/7998 but addresses some Java 2D API color related classes.

ICC_Profile can be made sealed, and the two extant sub-classes can be made final.

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Commit messages:
 - 8283701: Add final or sealed modifier to appropriate java.awt.color ICC_Profile API classes

Changes: https://git.openjdk.java.net/jdk/pull/8021/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=8021&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8283701
  Stats: 5 lines in 3 files changed: 2 ins; 0 del; 3 mod
  Patch: https://git.openjdk.java.net/jdk/pull/8021.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/8021/head:pull/8021

PR: https://git.openjdk.java.net/jdk/pull/8021