hg: jdk9/sandbox/langtools: 8167424: Various trivial fixes in build system

[chris.hegarty at oracle.com]

Changeset: a7bd119da966
Author:    ihse
Date:      2016-10-11 09:50 +0200
URL:       http://hg.openjdk.java.net/jdk9/sandbox/langtools/rev/a7bd119da966

8167424: Various trivial fixes in build system
Reviewed-by: erikj, tbell

! make/gensrc/GensrcCommon.gmk