Adding previews information to PLM UKM

chrome/browser/page_load_metrics/metrics_web_contents_observer.cc

Index: chrome/browser/page_load_metrics/metrics_web_contents_observer.cc
diff --git a/chrome/browser/page_load_metrics/metrics_web_contents_observer.cc b/chrome/browser/page_load_metrics/metrics_web_contents_observer.cc
index 4e0c875be5c35781d040a9342b34e9db571a1903..ea1875c1ec71922e66ef7d00465ac9585ee5ee13 100644
--- a/chrome/browser/page_load_metrics/metrics_web_contents_observer.cc
+++ b/chrome/browser/page_load_metrics/metrics_web_contents_observer.cc
@@ -684,4 +684,22 @@ void MetricsWebContentsObserver::TestingObserver::OnGoingAway() {
   observer_ = nullptr;
 }
 
+base::Optional<ukm::SourceId>
+MetricsWebContentsObserver::GetUKMSourceIdForNavigationHandle(
+    content::NavigationHandle* navigation_handle) {
+  base::Optional<ukm::SourceId> source_id;
+  auto it = provisional_loads_.find(navigation_handle);
+  if (it != provisional_loads_.end())
+    source_id = it->second->source_id();
+  return source_id;
+}
+
+base::Optional<ukm::SourceId>
+MetricsWebContentsObserver::GetUKMSourceForCommittedLoad() {
+  base::Optional<ukm::SourceId> source_id;
+  if (committed_load_)
+    source_id = committed_load_->source_id();
+  return source_id;
+}
+
 }  // namespace page_load_metrics