RFR: 8277215: Remove redundancy in ReferenceProcessor constructor args

[Albert Mingkun Yang]

Simple change of dropping one arg in the constructor.

Test: hotspot_gc

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Commit messages:
 - ref-ctor

Changes: https://git.openjdk.java.net/jdk/pull/6412/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=6412&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8277215
  Stats: 7 lines in 5 files changed: 0 ins; 5 del; 2 mod
  Patch: https://git.openjdk.java.net/jdk/pull/6412.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/6412/head:pull/6412

PR: https://git.openjdk.java.net/jdk/pull/6412