Initial UKMPageLoadMetricsObserver

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 2080bf23393b93780edcd8421dee1d1f39f7bc33..162d0790bdb31ebc9fee7b4ec44fb01ccea2669e 100644
--- a/chrome/browser/page_load_metrics/page_load_metrics_initialize.cc
+++ b/chrome/browser/page_load_metrics/page_load_metrics_initialize.cc
@@ -24,6 +24,7 @@
 #include "chrome/browser/page_load_metrics/observers/previews_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/protocol_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/service_worker_page_load_metrics_observer.h"
+#include "chrome/browser/page_load_metrics/observers/ukm_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/page_load_metrics_embedder_interface.h"
 #include "chrome/browser/page_load_metrics/page_load_tracker.h"
 #include "chrome/browser/prerender/prerender_contents.h"
@@ -84,6 +85,12 @@ void PageLoadMetricsEmbedder::RegisterObservers(
             web_contents_->GetBrowserContext()));
     tracker->AddObserver(base::MakeUnique<CssScanningMetricsObserver>());
     tracker->AddObserver(base::MakeUnique<ProtocolPageLoadMetricsObserver>());
+
+    std::unique_ptr<page_load_metrics::PageLoadMetricsObserver> ukm_observer =
+        UKMPageLoadMetricsObserver::CreateIfNeeded();
+    if (ukm_observer)
+      tracker->AddObserver(std::move(ukm_observer));
+
     std::unique_ptr<page_load_metrics::PageLoadMetricsObserver>
         no_state_prefetch_observer =
             NoStatePrefetchPageLoadMetricsObserver::CreateIfNeeded(