git: openjdk/jdk11u-dev: 8273826: Correct Manifest file name and NPE checks

[Goetz Lindenmaier]

Changeset: 9512c471
Author:    Goetz Lindenmaier <goetz at openjdk.org>
Date:      2021-10-11 11:58:15 +0000
URL:       https://git.openjdk.java.net/jdk11u-dev/commit/9512c471e9ab0830d8d5b2275803f59a0f073fcb

8273826: Correct Manifest file name and NPE checks

Reviewed-by: mdoerr
Backport-of: 03a8d342b86e720d3cba08d540182b4ab161fba3

! src/java.base/share/classes/java/util/jar/JarFile.java
! src/java.base/share/classes/java/util/jar/JarInputStream.java
! src/java.base/share/classes/java/util/jar/JarVerifier.java
! src/java.base/share/classes/sun/security/util/ManifestEntryVerifier.java
+ test/jdk/sun/security/tools/jarsigner/warnings/LowerCaseManifest.java