RFR: 8339341: SurfaceManager cacheMap retains strong references [v3]

[Nikita Gubarkov]

> I moved SurfaceDataProxy cache into a separate class.
> Now caching level is determined by placement of the SurfaceManager.ProxyCache object instead of a "proxy key". This cache "owns" proxies and therefore strong refs via them do not prevent the cache and GraphicsConfig from being detected as weakly reachable.

Nikita Gubarkov has updated the pull request incrementally with one additional commit since the last revision:

  Move surface data proxy cache into base CGraphicsConfig

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Changes:
  - all: https://git.openjdk.org/jdk/pull/20825/files
  - new: https://git.openjdk.org/jdk/pull/20825/files/3203ea9e..87866453

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=20825&range=02
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=20825&range=01-02

  Stats: 23 lines in 3 files changed: 7 ins; 14 del; 2 mod
  Patch: https://git.openjdk.org/jdk/pull/20825.diff
  Fetch: git fetch https://git.openjdk.org/jdk.git pull/20825/head:pull/20825

PR: https://git.openjdk.org/jdk/pull/20825