8202843: langtools ant build fails

Using default -source/-target settings when building langtools using the developer ant build.

Reviewed-by: mcimadamore

make/langtools/build.properties

@@ -24,9 +24,7 @@
 #
 
 #javac configuration for "normal build" (these will be passed to the bootstrap compiler):
-javac.opts = -XDignore.symbol.file=true -Xlint:all,-deprecation,-options,-exports -Werror -g:source,lines,vars
-javac.source = 9
-javac.target = 9
+javac.opts = -XDignore.symbol.file=true -Xlint:all,-deprecation,-exports -Werror -g:source,lines,vars
 
 #version used to compile build tools
 javac.build.opts = -XDignore.symbol.file=true -Xlint:all,-deprecation,-options -Werror -g:source,lines,vars

make/langtools/build.xml

@@ -232,7 +232,6 @@
         <pathconvert pathsep=" " property="source.files" refid="source.fileset"/>
         <echo file="${build.dir}/sources.txt">${source.files}</echo>
         <exec executable="${langtools.jdk.home}/bin/javac" failonerror="true">
-            <arg line="-source ${javac.source} -target ${javac.target}" />
             <arg value="-d" />
             <arg value="${build.modules}" />
             <arg line="${javac.opts}" />