[testing] fix vm-finder on macs.

buildScripts/vm-finder.ant.xml

@@ -60,7 +60,8 @@ and rerun the build; this build is capable of finding VMs automatically on many
 		<fail unless="find-vm.version">Set property find-vm.version first</fail>
 		<local name="java_home.answer" />
 		<local name="java_home.result" />
-		<exec executable="${exe.java_home}" errorproperty="discard" outputproperty="java_home.answer" failifexecutionfails="false" resultproperty="java_home.result">
+		<exec newenvironment="true" executable="${exe.java_home}" errorproperty="discard" outputproperty="java_home.answer" failifexecutionfails="false" resultproperty="java_home.result">
+			<env key="floobargle" value="FOO" /> <!-- we do not want JAVA_HOME to be set. This requires newenvironment="true" AND some sort of env value -->
 			<arg value="-v" />
 			<arg value="${find-vm.version}" />
 		</exec>