I think that there is a bug in Servo when compiled into a shared library. This
is different than creating a shared library just for libservo-- I'm trying to
make a shared library that contains libservo PLUS some of my own code.

This is a short but complete program that illustrates the problem. It consists
of a shared library that is written in Rust, plus a Python component that tries
to open the library with dlopen. The shared library contains just libservo and
no code of its own.

To reproduce the bug (on Linux)
* Make sure you have the right Rust compiler version for Servo commit 2f8fa32.
* Run "cargo build" in this directory to build the Rust component.
* Run ./main.py in this directory.

Expected results:
Nothing should happen, the program should just silently exit because it doesn't
do anything.

Actual results:
The dlopen will fail on librust_component.so, because it has undefined symbols.