hgweb: handle None from templatedir() equally bad in webcommands.py The following paragraph is based just on my reading of the code; I have not tried to test it. Before my recent work on templates in frozen binaries, it seems both `hgwebdir_mod.py` and `webcommands.py` would pass in an empty list into `staticfile()` when running in a frozen binary. That would then result in a variable in that function (`path`) not getting bound before its first use. I then changed that without thinking in D8786 so we passed a `None` value into the function, which made it break in another way (trying to iterate over `None`). Then I tried to fix it up in D8810, but I only changed `hgwebdir_mod.py` for some reason, and it still doesn't actually work in frozen binaries (which seems fair, since was broken before my changes too). This patch just replicates the half-assed "fix" from D8810 in `webcommands.py`, so they look more similar so I can start refactoring them in the same way. Differential Revision: https://phab.mercurial-scm.org/D8933