RFR: 8318113: CSS.BackgroundImage doesn't implement equals [v3]

[Prasanta Sadhukhan]

> CSSBackgroundImage.equals() is implemented

Prasanta Sadhukhan has updated the pull request incrementally with one additional commit since the last revision:

  Use Objects.hashCode and add bugid

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Changes:
  - all: https://git.openjdk.org/jdk/pull/16613/files
  - new: https://git.openjdk.org/jdk/pull/16613/files/b6de4b9e..c656e9ae

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=16613&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=16613&range=01-02

  Stats: 2 lines in 1 file changed: 0 ins; 0 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/16613.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/16613/head:pull/16613

PR: https://git.openjdk.org/jdk/pull/16613