RFR: JDK-8293412 Remove unnecessary java.security.egd overrides [v4]

[Mark Powers]

> https://bugs.openjdk.org/browse/JDK-8293412

Mark Powers has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains eight additional commits since the last revision:

 - Merge
 - javadoc update
 - yes we need /dev/urandom
 - Merge
 - Merge
 - second iteration
 - Merge
 - first iteration

-------------

Changes:
  - all: https://git.openjdk.org/jdk/pull/10716/files
  - new: https://git.openjdk.org/jdk/pull/10716/files/80be7e6b..8076b616

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk&pr=10716&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk&pr=10716&range=02-03

  Stats: 89795 lines in 1773 files changed: 38018 ins; 35347 del; 16430 mod
  Patch: https://git.openjdk.org/jdk/pull/10716.diff
  Fetch: git fetch https://git.openjdk.org/jdk pull/10716/head:pull/10716

PR: https://git.openjdk.org/jdk/pull/10716