Gitlab: unable to determine project name

Created by: lguychard

From Sentry: https://sentry.io/organizations/sourcegraph/issues/846569138/?project=1334031&query=extension_version%3A19.10.9.1226+project+name&statsPeriod=14d

This seems to happen on the search page, when viewing code search results, because the search page has no side bar, which contains the project name link ('.context-header a'). But also on other pages that are not /search.