Use the proper 'off' default for COMP_THEME_DIR.

lms/envs/common.py

@@ -452,7 +452,7 @@ COURSES_ROOT = ENV_ROOT / "data"
 DATA_DIR = COURSES_ROOT
 
 # comprehensive theming system
-COMP_THEME_DIR = None
+COMP_THEME_DIR = ""
 
 # TODO: Remove the rest of the sys.path modification here and in cms/envs/common.py
 sys.path.append(REPO_ROOT)

pavelib/assets.py

@@ -45,7 +45,7 @@ def configure_paths():
             css_dir.mkdir_p()
             SASS_DIRS.append(sass_dir)
 
-    if edxapp_env.env_tokens.get("COMP_THEME_DIR", None):
+    if edxapp_env.env_tokens.get("COMP_THEME_DIR", ""):
         theme_dir = path(edxapp_env.env_tokens["COMP_THEME_DIR"])
         lms_sass = theme_dir / "lms" / "static" / "sass"
         lms_css = theme_dir / "lms" / "static" / "css"