This CL include changes in the registrar console that makes it possible to designate an abuse contact in domain WHOIS record, per ICANN's CL&D requirement.

Frontend validation: ensures that only one WHOIS abuse contact exist per registrar. Any existing WHOIS abuse contact will be overridden when a new one is designated.

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Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=155289097

java/google/registry/ui/externs/json.js

@@ -108,6 +108,7 @@ registry.json.RegistrarAddress;
  *   emailAddress: string,
  *   visibleInWhoisAsAdmin: boolean,
  *   visibleInWhoisAsTech: boolean,
+ *   visibleInDomainWhoisAsAbuse: boolean,
  *   phoneNumber: (string?|undefined),
  *   faxNumber: (string?|undefined),
  *   types: (string?|undefined)