hg: jdk9/sandbox/jdk: Commit remaining files

[aleksey.shipilev at oracle.com]

Changeset: 9b93ad322ef2
Author:    shade
Date:      2015-08-18 22:53 +0300
URL:       http://hg.openjdk.java.net/jdk9/sandbox/jdk/rev/9b93ad322ef2

Commit remaining files

+ src/java.base/share/classes/java/lang/StringConcatHelper.java
+ src/java.base/share/classes/java/lang/invoke/StringConcatFactory.java
+ test/java/lang/String/ImplicitStringConcat.java