RFR: 8282240: Add _name field to Method for NOT_PRODUCT only

[Coleen Phillimore]

Whenever I'm debugging I really wish I knew the name of the method that I'm looking at, so I added this field in not-product.
Tested with tier1 on Oracle platforms.

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Commit messages:
 - 8282240: Add _name field to Method for NOT_PRODUCT only

Changes: https://git.openjdk.java.net/jdk/pull/7608/files
 Webrev: https://webrevs.openjdk.java.net/?repo=jdk&pr=7608&range=00
  Issue: https://bugs.openjdk.java.net/browse/JDK-8282240
  Stats: 14 lines in 4 files changed: 10 ins; 0 del; 4 mod
  Patch: https://git.openjdk.java.net/jdk/pull/7608.diff
  Fetch: git fetch https://git.openjdk.java.net/jdk pull/7608/head:pull/7608

PR: https://git.openjdk.java.net/jdk/pull/7608