Add compiler option for wide string encoding

This is more of a workaround, since I expect users that try to define their own
messages with wide strings to run into the same issue.
It would be nice if they didn't also have to specify an encoding.

Signed-off-by: Jacob Perron <jacob@openrobotics.org>

Author: jacobperron

rosidl_generator_java/CMakeLists.txt

@@ -38,6 +38,10 @@ if(BUILD_TESTING)
   find_package(ament_lint_auto REQUIRED)
   ament_lint_auto_find_test_dependencies()
 
+  # TODO(jacobperron): This fixes generating messages with wstrings.
+  # Figure out why this is needed as of Foxy, and how we can remove this workaround
+  set(CMAKE_JAVA_COMPILE_FLAGS "-encoding" "ISO-8859-1")
+
   include(cmake/register_java.cmake)
   include(cmake/rosidl_generator_java_get_typesupports.cmake)