Fail gracefully

Author: AA-Turner

PC/layout/support/build_details.py

@@ -20,12 +20,16 @@
 try:
     sys.path.insert(0, str(TOOLS_BUILD_DIR))
     import generate_build_details
+except ImportError:
+    generate_build_details = None
 finally:
     sys.path = sys_path
     del sys_path
 
 
 def write_relative_build_details(out_path, base_path):
+    if generate_build_details is None:
+        return
     generate_build_details.write_build_details(
         schema_version=PEP739_SCHEMA_VERSION,
         base_path=base_path,