git: openjdk/loom: fibers: Add threshold to pinned event

[duke]

Changeset: d44d568e
Author:    Alan Bateman <alan.bateman at oracle.com>
Date:      2021-04-29 08:08:15 +0000
URL:       https://git.openjdk.java.net/loom/commit/d44d568eecefd9dd47ec595e13ab916afd1f1747

Add threshold to pinned event

! src/java.base/share/classes/java/lang/VirtualThread.java
! src/jdk.jfr/share/conf/jfr/default.jfc
! src/jdk.jfr/share/conf/jfr/profile.jfc
! test/jdk/jdk/jfr/event/metadata/TestDefaultConfigurations.java
! test/lib/jdk/test/lib/jfr/EventNames.java