[OpenJDK 2D-Dev] RFR: 8263051: Modernize the code in the java.awt.color package

[Sergey Bylokhov]

This is mostly the polish of the different methods in this package.

Most changes are spacing and formatting, plus code simplification. No semantic changes, mach5 is green.

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

Commit messages:
 - Unify theTagSignature vs tagSignature
 - Update ICC_Profile.java
 - Initial fix

Changes: https://git.openjdk.java.net/jdk/pull/2855/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=2855&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8263051
  Stats: 420 lines in 4 files changed: 9 ins; 255 del; 156 mod
  Patch: https://git.openjdk.java.net/jdk/pull/2855.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/2855/head:pull/2855

PR: https://git.openjdk.java.net/jdk/pull/2855