This no longer works on all interfaces (no safe_union support) and
future/existing efforts are focusing on making the hidl-gen output
itself more usable for existing tools.

For instance, here are some of the things being done or which have
already been done:
- copy comments from HIDL files to their generated outputs
- adding comments to HIDL-generated code

Using these mechanisms, we may consider something like doxygen (or just
increased usages of tools in the tree that directly look at the
generated files, e.g. using compdb, AIDEgen, or other technologies).

Bug: N/A
Test: N/A
Change-Id: Ibd5e7c04d9c2ff0d6425100ea79a0a66d1b9a49e