Openttd newly included file error_func.h defines two new macros named
FatalError() and UserError(). FatalError() unfortunatly colides with a
method declared in jni.h
jni.h makes its way into Openttd code by being present at SDL_android.h;
Since knownledge of jni.h is not needed for Openttd code the adopted
solution was to remove jni.h from SDL_android.h and forward declare any
of its usages. Akin to pimpl pattern.