hg: jdk/sandbox: Add streaming support for repository migration

[erik.gahlin at oracle.com]

Changeset: 5693904ecbde
Author:    egahlin
Date:      2019-08-15 02:58 +0200
URL:       https://hg.openjdk.java.net/jdk/sandbox/rev/5693904ecbde

Add streaming support for repository migration

! src/jdk.jfr/share/classes/jdk/jfr/internal/consumer/RepositoryFiles.java
+ test/jdk/jdk/jfr/api/consumer/streaming/TestRepositoryMigration.java