RFR: JDK-8290011: IGV: Remove dead code and cleanup [v5]

[Tobias Holenstein]

> Remove dead code from the IGV code base. There are many unused or redundant functions in the code

Tobias Holenstein has updated the pull request incrementally with two additional commits since the last revision:

 - Merge branch 'JDK-8290011' of github.com:tobiasholenstein/jdk into JDK-8290011
 - remove unsued getPropertyComparator()

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Changes:
  - all: https://git.openjdk.org/jdk/pull/10197/files
  - new: https://git.openjdk.org/jdk/pull/10197/files/23ddbf98..9692b5f5

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=10197&range=04
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=10197&range=03-04

  Stats: 32 lines in 1 file changed: 0 ins; 32 del; 0 mod
  Patch: https://git.openjdk.org/jdk/pull/10197.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10197/head:pull/10197

PR: https://git.openjdk.org/jdk/pull/10197