seed ROS_MAVEN_REPOSITORY when necessary.

cmake/rosjava.cmake.em

@@ -45,11 +45,17 @@ endmacro()
 # override a user setting.
 macro(_rosjava_env)
     set(ROS_MAVEN_DEPLOYMENT_REPOSITORY $ENV{ROS_MAVEN_DEPLOYMENT_REPOSITORY})
+    set(ROS_MAVEN_REPOSITORY $ENV{ROS_MAVEN_REPOSITORY})
     if(NOT ROS_MAVEN_DEPLOYMENT_REPOSITORY)
         set(ROSJAVA_ENV "ROS_MAVEN_DEPLOYMENT_REPOSITORY=${CATKIN_DEVEL_PREFIX}/${CATKIN_GLOBAL_MAVEN_DESTINATION}")
     else()
         set(ROSJAVA_ENV "ROS_MAVEN_DEPLOYMENT_REPOSITORY=${ROS_MAVEN_DEPLOYMENT_REPOSITORY}")
     endif()
+    if(NOT ROS_MAVEN_REPOSITORY)
+        list(APPEND ROSJAVA_ENV "ROS_MAVEN_REPOSITORY=https://github.com/rosjava/rosjava_mvn_repo/raw/master")
+    else()
+        set(ROSJAVA_ENV "ROS_MAVEN_REPOSITORY=${ROS_MAVEN_REPOSITORY}")
+    endif()
     # The build farm won't let you access /root/.gradle, so redirect it somewhere practical here.
     if(DEFINED CATKIN_BUILD_BINARY_PACKAGE)
       list(APPEND ROSJAVA_ENV "GRADLE_USER_HOME=${CATKIN_DEVEL_PREFIX}/${CATKIN_GLOBAL_GRADLE_DESTINATION}")