RFR: 8336389: Infinite loop occurs while resolving lookups [v3]

[John Hendrikx]

> Fixes an infinite loop that can occur while resolving lookups.
> 
> There were 2 bugs:
> - A `contains` check was done on some value X, but then a value Y was added to the set used to track duplicates
> - The `Set` to track duplicates was cleared in some recursive calls, meaning that the caller (which may be processing multiple values in a loop) would end up with an empty set, losing track of what was visited so far
> 
> Also removed a redundant `null` check (an NPE would have occurred before it could reach that code).

John Hendrikx has updated the pull request with a new target base due to a merge or a rebase. The pull request now contains three commits:

 - Merge branch 'master' of https://git.openjdk.org/jfx into
   feature/fix-stackoverflow-in-resolve-lookups
 - Fix formatting and spelling
 - Fix loop detection in resolveLookups

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Changes: https://git.openjdk.org/jfx/pull/1505/files
  Webrev: https://webrevs.openjdk.org/?repo=jfx&pr=1505&range=02
  Stats: 68 lines in 2 files changed: 55 ins; 9 del; 4 mod
  Patch: https://git.openjdk.org/jfx/pull/1505.diff
  Fetch: git fetch https://git.openjdk.org/jfx.git pull/1505/head:pull/1505

PR: https://git.openjdk.org/jfx/pull/1505