Persist EffectiveConnectionType in UKM on navigation start.

chrome/browser/page_load_metrics/page_load_metrics_initialize.cc

Index: chrome/browser/page_load_metrics/page_load_metrics_initialize.cc
diff --git a/chrome/browser/page_load_metrics/page_load_metrics_initialize.cc b/chrome/browser/page_load_metrics/page_load_metrics_initialize.cc
index 3af2ffdd7c944087f97252bee700dfd963bb1a8a..ffca7008daa12fb5af7de0a9b2cb6b609782d498 100644
--- a/chrome/browser/page_load_metrics/page_load_metrics_initialize.cc
+++ b/chrome/browser/page_load_metrics/page_load_metrics_initialize.cc
@@ -92,7 +92,7 @@ void PageLoadMetricsEmbedder::RegisterObservers(
     tracker->AddObserver(base::MakeUnique<TabRestorePageLoadMetricsObserver>());
 
     std::unique_ptr<page_load_metrics::PageLoadMetricsObserver> ukm_observer =
-        UkmPageLoadMetricsObserver::CreateIfNeeded();
+        UkmPageLoadMetricsObserver::CreateIfNeeded(web_contents_);
     if (ukm_observer)
       tracker->AddObserver(std::move(ukm_observer));