[Tab Metrics] Measure FP, FCP and FMP for Foreground Tab during Session Restore

chrome/browser/page_load_metrics/page_load_metrics_initialize.cc

 // Copyright 2015 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/page_load_metrics_initialize.h"
 
 #include <memory>
 #include <utility>
 
 #include "base/macros.h"
 #include "base/memory/ptr_util.h"
 #include "base/timer/timer.h"
+#include "build/build_config.h"
 #include "chrome/browser/page_load_metrics/metrics_web_contents_observer.h"
 #if defined(OS_ANDROID)
 #include "chrome/browser/page_load_metrics/observers/android_page_load_metrics_observer.h"
 #endif  // OS_ANDROID
 #include "chrome/browser/page_load_metrics/observers/aborts_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/ads_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/amp_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/core_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/css_scanning_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/data_reduction_proxy_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/delay_navigation_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/document_write_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/from_gws_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/google_captcha_observer.h"
 #include "chrome/browser/page_load_metrics/observers/https_engagement_metrics/https_engagement_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/loading_predictor_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/local_network_requests_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/lofi_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/media_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/multi_tab_loading_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/no_state_prefetch_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/omnibox_suggestion_used_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/prerender_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/previews_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/previews_ukm_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/session_restore_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/subresource_filter_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/tab_restore_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/ukm_page_load_metrics_observer.h"
 #include "chrome/browser/page_load_metrics/observers/use_counter_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"
 #include "chrome/browser/profiles/profile.h"
 #include "chrome/browser/search/search.h"
 #include "components/rappor/rappor_service_impl.h"
@@ skipping 80 matching lines @@
 #if defined(OS_ANDROID)
     tracker->AddObserver(
         base::MakeUnique<AndroidPageLoadMetricsObserver>(web_contents_));
 #endif  // OS_ANDROID
     std::unique_ptr<page_load_metrics::PageLoadMetricsObserver>
         loading_predictor_observer =
             LoadingPredictorPageLoadMetricsObserver::CreateIfNeeded(
                 web_contents_);
     if (loading_predictor_observer)
       tracker->AddObserver(std::move(loading_predictor_observer));
+#if !defined(OS_ANDROID)

[Charlie Harrison, 2017/08/07 14:30:08]

While you're here could you also gate the #includes by this #ifdef? That way we
don't have to pull in the session restore observer on android, and the android
observer on desktop.

[ducbui, 2017/08/08 16:29:49]

Done. Thanks for the suggestion!

+    tracker->AddObserver(
+        base::MakeUnique<SessionRestorePageLoadMetricsObserver>());
+#endif
     tracker->AddObserver(
         base::MakeUnique<LocalNetworkRequestsPageLoadMetricsObserver>());
   } else {
     std::unique_ptr<page_load_metrics::PageLoadMetricsObserver>
         prerender_observer =
             PrerenderPageLoadMetricsObserver::CreateIfNeeded(web_contents_);
     if (prerender_observer)
       tracker->AddObserver(std::move(prerender_observer));
   }
   tracker->AddObserver(
@@ skipping 21 matching lines @@
 
 }  // namespace
 
 void InitializePageLoadMetricsForWebContents(
     content::WebContents* web_contents) {
   page_load_metrics::MetricsWebContentsObserver::CreateForWebContents(
       web_contents, base::MakeUnique<PageLoadMetricsEmbedder>(web_contents));
 }
 
 }  // namespace chrome