[jdk11u-dev] RFR: 8300079: SIGSEGV in LibraryCallKit::inline_string_copy due to constant NULL src argument

[Goetz Lindenmaier]

I had to resolve three chunks. 

Also, I replaced nullptr by NULL in one place.

-------------

Commit messages:
 - Backport 52324b55fb7be2cd1ba9e843ece93375ac23649c

Changes: https://git.openjdk.org/jdk11u-dev/pull/1911/files
 Webrev: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=1911&range=00
  Issue: https://bugs.openjdk.org/browse/JDK-8300079
  Stats: 85 lines in 2 files changed: 61 ins; 0 del; 24 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/1911.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/1911/head:pull/1911

PR: https://git.openjdk.org/jdk11u-dev/pull/1911