Hi, it's me from the future. Please use the new bazel feature from the previous message.
It turned out that my dirty trick has a fatal flaw. Don't ask how I know. :/
The c++ build rules have additional smarts, and will prune the included file from the set of deps needed to rebuild the target. The end result is, you will get your artifact built initially, but if the artifact changes, the targets depending on them will not be rebuilt. Which is not a good thing to have in bazel. I was also told that the approach might work with `textual_hdrs`, but I haven't tried.