[jdk11u-dev] RFR: 8273914: Indy string concat changes order of operations [v4]

[Liam Miller-Cushon]

> This is a backport of [JDK-8273914: Indy string concat changes order of operations](https://bugs.openjdk.org/browse/JDK-8273914).
> 
> The patch applied cleanly. I downgrade the class file major version in the `.jasm` test inputs for compatibility with JDK 11.
> 
> Testing: tier1 langtools tests

Liam Miller-Cushon has updated the pull request with a new target base due to a merge or a rebase. The incremental webrev excludes the unrelated changes brought in by the merge/rebase. The pull request contains four additional commits since the last revision:

 - Merge remote-tracking branch 'upstream/master' into backport-JDK-8273914
 - Downgrade major version for jasm test inputs
 - Merge remote-tracking branch 'upstream/master' into backport-JDK-8273914
 - Backport cfee4512f7048e9cf440078e9eb87d37c7ebcdd9

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

Changes:
  - all: https://git.openjdk.org/jdk11u-dev/pull/2933/files
  - new: https://git.openjdk.org/jdk11u-dev/pull/2933/files/cd858cfa..a57aad56

Webrevs:
 - full: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2933&range=03
 - incr: https://webrevs.openjdk.org/?repo=jdk11u-dev&pr=2933&range=02-03

  Stats: 302 lines in 16 files changed: 142 ins; 52 del; 108 mod
  Patch: https://git.openjdk.org/jdk11u-dev/pull/2933.diff
  Fetch: git fetch https://git.openjdk.org/jdk11u-dev.git pull/2933/head:pull/2933

PR: https://git.openjdk.org/jdk11u-dev/pull/2933