Add support for logging additional metrics in UKM.

chrome/browser/page_load_metrics/observers/ukm_page_load_metrics_observer.cc

 // Copyright 2017 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/page_load_metrics/observers/ukm_page_load_metrics_observer.h"
 #include "chrome/browser/browser_process.h"
 #include "components/ukm/ukm_service.h"
 #include "components/ukm/ukm_source.h"
 
 // static
 std::unique_ptr<page_load_metrics::PageLoadMetricsObserver>
 UkmPageLoadMetricsObserver::CreateIfNeeded() {
   if (!g_browser_process->ukm_service()) {
     return nullptr;
   }
 
   return base::MakeUnique<UkmPageLoadMetricsObserver>();
 }
 
-UkmPageLoadMetricsObserver::UkmPageLoadMetricsObserver() {}
+UkmPageLoadMetricsObserver::UkmPageLoadMetricsObserver()
+    : source_(base::MakeUnique<ukm::UkmSource>()) {}
+
+UkmPageLoadMetricsObserver::~UkmPageLoadMetricsObserver() = default;
 
 UkmPageLoadMetricsObserver::ObservePolicy UkmPageLoadMetricsObserver::OnStart(
     content::NavigationHandle* navigation_handle,
     const GURL& currently_committed_url,
     bool started_in_foreground) {
+  source_->set_url(navigation_handle->GetURL());
+  navigation_start_ = navigation_handle->NavigationStart();
   return started_in_foreground ? CONTINUE_OBSERVING : STOP_OBSERVING;
 }
 
 UkmPageLoadMetricsObserver::ObservePolicy
 UkmPageLoadMetricsObserver::FlushMetricsOnAppEnterBackground(
     const page_load_metrics::PageLoadTiming& timing,
     const page_load_metrics::PageLoadExtraInfo& info) {
-  SendMetricsToUkm(timing, info);
+  PopulateTiming(timing);
+  PopulatePageLoadExtraInfo(info);
+
+  // FlushMetricsOnAppEnterBackground may be invoked in cases where the page
+  // load isn't 'done', but Chrome is being backgrounded and may be killed
+  // without any subsequent noifications. In these cases, if we don't have an
+  // end time already, we synthesize an end time using the current time.
+  if (!source_->total_time())
+    source_->set_total_time(base::TimeTicks::Now() - navigation_start_);
+
+  SendMetricsToUkm();
   return STOP_OBSERVING;
 }
 
 UkmPageLoadMetricsObserver::ObservePolicy UkmPageLoadMetricsObserver::OnHidden(
     const page_load_metrics::PageLoadTiming& timing,
     const page_load_metrics::PageLoadExtraInfo& info) {
-  SendMetricsToUkm(timing, info);
+  PopulateTiming(timing);
+  PopulatePageLoadExtraInfo(info);
+  SendMetricsToUkm();
   return STOP_OBSERVING;
 }
 
+void UkmPageLoadMetricsObserver::OnFailedProvisionalLoad(
+    const page_load_metrics::FailedProvisionalLoadInfo& failed_load_info,
+    const page_load_metrics::PageLoadExtraInfo& extra_info) {
+  PopulatePageLoadExtraInfo(extra_info);
+  SendMetricsToUkm();
+}
+
 void UkmPageLoadMetricsObserver::OnComplete(
     const page_load_metrics::PageLoadTiming& timing,
     const page_load_metrics::PageLoadExtraInfo& info) {
-  SendMetricsToUkm(timing, info);
+  PopulateTiming(timing);
+  PopulatePageLoadExtraInfo(info);
+  SendMetricsToUkm();
 }
 
-void UkmPageLoadMetricsObserver::SendMetricsToUkm(
-    const page_load_metrics::PageLoadTiming& timing,
+void UkmPageLoadMetricsObserver::PopulateTiming(
+    const page_load_metrics::PageLoadTiming& timing) {
+  if (timing.parse_start)
+    source_->set_parse_start(timing.parse_start.value());
+  if (timing.first_contentful_paint)
+    source_->set_first_contentful_paint(timing.first_contentful_paint.value());
+  if (timing.first_meaningful_paint)
+    source_->set_first_meaningful_paint(timing.first_meaningful_paint.value());
+}
+
+void UkmPageLoadMetricsObserver::PopulatePageLoadExtraInfo(
     const page_load_metrics::PageLoadExtraInfo& info) {
-  if (!info.did_commit || !timing.first_contentful_paint)
-    return;
+  source_->set_url(info.url);
 
+  if (info.first_background_time) {
+    source_->set_total_time(info.first_background_time.value());
+  } else if (info.page_end_time) {
+    source_->set_total_time(info.page_end_time.value());
+  }
+}
+
+void UkmPageLoadMetricsObserver::SendMetricsToUkm() {
   ukm::UkmService* ukm_service = g_browser_process->ukm_service();
   DCHECK(ukm_service);
-
-  std::unique_ptr<ukm::UkmSource> source = base::MakeUnique<ukm::UkmSource>();
-  source->set_committed_url(info.url);
-  source->set_first_contentful_paint(timing.first_contentful_paint.value());
-
-  ukm_service->RecordSource(std::move(source));
+  ukm_service->RecordSource(std::move(source_));
+  source_.reset();
 }