Avoid breaking pages without dtl_sources
Avoid breaking pages without dtl_sources


Former-commit-id: d9501d9317101fa703db9bbce54f7ebacf67fa77
JeffreyBLewis/WebVoteView,JeffreyBLewis/WebVoteView,JeffreyBLewis/WebVoteView,JeffreyBLewis/WebVoteView