content/shell/browser/content_shell_utility_manifest_overlay.json

{
  "name": "content_utility",
  "interface_provider_specs": {
    "service_manager:connector": {
      "provides": {
        "browser": [
          "content::mojom::PowerMonitorTest",
          "content::mojom::TestService"
        ]
      }
    }
  }
}