[jdk17] RFR: JDK-8268826: Cleanup Override in Context-Specific Deserialization Filters [v4]

[Roger Riggs]

> Remove the unnecessary special case "OVERRIDE" in jdk.serialFilterFactory property.
> Fix description in the example of a filter allowing platform classes.
> Suppress some warnings about use of SecurityManager in tests.

Roger Riggs has updated the pull request incrementally with one additional commit since the last revision:

  Improve exception cases and messages when the jdk.serialFilterFactory
  is misconfigured and test those faults.
  Fix typo in java.security-extra-factory test config

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Changes:
  - all: https://git.openjdk.java.net/jdk17/pull/85/files
  - new: https://git.openjdk.java.net/jdk17/pull/85/files/cf6f5edb..0ac107e4

Webrevs:
 - full: https://webrevs.openjdk.java.net/?repo=jdk17&pr=85&range=03
 - incr: https://webrevs.openjdk.java.net/?repo=jdk17&pr=85&range=02-03

  Stats: 121 lines in 4 files changed: 112 ins; 4 del; 5 mod
  Patch: https://git.openjdk.java.net/jdk17/pull/85.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk17 pull/85/head:pull/85

PR: https://git.openjdk.java.net/jdk17/pull/85