hg: panama/dev: Automatic merge with default

[maurizio.cimadamore at oracle.com]

Changeset: 2ffe8ee298a1
Author:    mcimadamore
Date:      2018-12-26 22:09 +0100
URL:       http://hg.openjdk.java.net/panama/dev/rev/2ffe8ee298a1

Automatic merge with default

! make/autoconf/basics.m4
! make/autoconf/spec.gmk.in
- src/hotspot/share/runtime/arguments_ext.hpp
- src/hotspot/share/services/diagnosticCommand_ext.hpp
- test/langtools/jdk/javadoc/doclet/lib/JavadocTester.java