Remove unused build property for JNI (#9924)

Author: niloc132

common.ant.xml

@@ -41,15 +41,13 @@
   <property name="gwt.build" location="${gwt.root}/build"/>
   <property name="gwt.build.out" location="${gwt.build}/out"/>
   <property name="gwt.build.lib" location="${gwt.build}/lib"/>
-  <property name="gwt.build.jni" location="${gwt.build}/jni"/>
   <property name="gwt.build.staging" location="${gwt.build}/staging"/>
   <property name="gwt.build.dist" location="${gwt.build}/dist"/>
   <!-- gwt.threadsPerProcessor supercedes gwt.threadCount unless set to 0 -->
   <property name="gwt.threadsPerProcessor" value="1"/>
   <property name="gwt.threadCount" value="1"/>
   <property name="project.build" location="${gwt.build.out}/${project.tail}"/>
   <property name="project.lib" location="${gwt.build.lib}/gwt-${ant.project.name}.jar"/>
-  <property name="project.jni" location="${gwt.build}/${project.tail}"/>
   <property name="javac.out" location="${project.build}/bin"/>
   <property name="javac.junit.out" location="${project.build}/bin-test"/>
   <property name="javac.emma.out" location="${project.build}/bin-emma"/>