hg: jdk9/sandbox/jdk: Introduce -XstringConcat: javac option

[aleksey.shipilev at oracle.com]

Changeset: 120443e54c6e
Author:    shade
Date:      2015-08-27 21:39 +0300
URL:       http://hg.openjdk.java.net/jdk9/sandbox/jdk/rev/120443e54c6e

Introduce -XstringConcat: javac option

! test/java/lang/String/ImplicitStringConcat.java
! test/java/lang/String/ImplicitStringConcatMany.java
! test/java/lang/String/ImplicitStringConcatShapes.java