hg: jdk/jdk: 8222484: Specialize generation of simple String concatenation expressions

[claes.redestad at oracle.com]

Changeset: 5fa7fbddfe9d
Author:    redestad
Date:      2019-04-17 00:06 +0200
URL:       http://hg.openjdk.java.net/jdk/jdk/rev/5fa7fbddfe9d

8222484: Specialize generation of simple String concatenation expressions
Reviewed-by: jrose, jlaskey

! make/jdk/src/classes/build/tools/classlist/HelloClasslist.java
! src/java.base/share/classes/java/lang/String.java
! src/java.base/share/classes/java/lang/StringConcatHelper.java
! src/java.base/share/classes/java/lang/invoke/StringConcatFactory.java
! test/micro/org/openjdk/bench/java/lang/StringConcat.java