Fix Python docgen

The old package directory handling was stale in grpcio's setup.py
command support module and docgen had a typo.

src/python/grpcio/commands.py

@@ -64,7 +64,7 @@ class SphinxDocumentation(setuptools.Command):
     import sphinx.apidoc
     metadata = self.distribution.metadata
     src_dir = os.path.join(
-        os.getcwd(), self.distribution.package_dir['grpc'])
+        os.getcwd(), self.distribution.package_dir[''], 'grpc')
     sys.path.append(src_dir)
     sphinx.apidoc.main([
         '', '--force', '--full', '-H', metadata.name, '-A', metadata.author,

tools/distrib/python/docgen.py

@@ -81,7 +81,7 @@ if args.submit:
   assert args.doc_branch
   github_user = args.gh_user
   github_repository_owner = (
-      args.gh_repo_owner if args.gh_repo_owner else gh_user)
+      args.gh_repo_owner if args.gh_repo_owner else args.gh_user)
   # Create a temporary directory out of tree, checkout gh-pages from the
   # specified repository, edit it, and push it. It's up to the user to then go
   # onto GitHub and make a PR against grpc/grpc:gh-pages.