The partial backport of the enhancement, JDK-4947890, has caused the default vendor in OpenJDK 11u to change from "Oracle Corporation" to "N/A".

With 11.0.8-ga:

$ /usr/lib/jvm/java-11-openjdk/bin/java -version
openjdk version "11.0.8" 2020-07-14 LTS
OpenJDK Runtime Environment 18.9 (build 11.0.8+10-LTS)
OpenJDK 64-Bit Server VM 18.9 (build 11.0.8+10-LTS, mixed mode, sharing)

$ /usr/lib/jvm/java-11-openjdk/bin/java -XshowSettings:properties -version 2>&1 | grep java.vendor
    java.vendor = N/A
    java.vendor.url = https://openjdk.java.net/
    java.vendor.url.bug = https://bugreport.java.com/bugreport/
    java.vendor.version = 18.9

With a local build of 11.0.7-ga:

$ ~/builder/11u/images/jdk/bin/java -version
openjdk version "11.0.7-internal" 2020-04-14
OpenJDK Runtime Environment (fastdebug build 11.0.7-internal+0-adhoc.ahughes.jdk11)
OpenJDK 64-Bit Server VM (fastdebug build 11.0.7-internal+0-adhoc.ahughes.jdk11, mixed mode)

$ ~/builder/11u/images/jdk/bin/java -XshowSettings:properties -version 2>&1 | grep java.vendor
    java.vendor = Oracle Corporation
    java.vendor.url = http://java.oracle.com/
    java.vendor.url.bug = http://bugreport.java.com/bugreport/

The change can be clearly seen in the changeset for JDK-8242154 where the #define VENDOR "Oracle Corporation" is removed from System.c, but, unlike with VENDOR_URL and VENDOR_URL_BUG, the value is not transferred to the key-value pairs in make/autoconf/version-numbers.

While this may be appropriate in a new release (this was originally a change for 12 GA), I don't think this is appropriate for a long-term stable release.