Instead of using a collection of Python scripts to generate the artifacts we
want to distribute from this repository, we should just use the build system.
This CL adds a top-level |dist| target that creates these artifacts in a "dist"
directory of the build output.
Mojo is an effort to extract a common platform out of Chrome's renderer and
plugin processes that can support multiple types of sandboxed content, such as
HTML, Pepper, or NaCl.