git: openjdk/jdk13u-dev: 8196969: JTreg Failure: serviceability/sa/ClhsdbJstack.java causes NPE

[Yuri Nesterenko]

Changeset: 962ff982
Author:    Ekaterina Vergizova <evergizova at openjdk.org>
Committer: Yuri Nesterenko <yan at openjdk.org>
Date:      2021-02-09 10:52:59 +0000
URL:       https://git.openjdk.java.net/jdk13u-dev/commit/962ff982

8196969: JTreg Failure: serviceability/sa/ClhsdbJstack.java causes NPE

Account for serialized null scopes in NMethod

Backport-of: c4f5c4fe9ba9c7ee9f46da309d8bff4ecf771f49

! src/jdk.hotspot.agent/share/classes/sun/jvm/hotspot/code/NMethod.java
+ test/hotspot/jtreg/serviceability/sa/ClhsdbJstackXcompStress.java
+ test/hotspot/jtreg/serviceability/sa/LingeredAppWithRecComputation.java