Cleanup navigation restart metrics in previews

This got missed in the original cleanup.

Change-Id: Iaa48d54b78c18648c8a24d79cb9b3679a4e573fd
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1988722Reviewed-by: Ryan Sturm <ryansturm@chromium.org>
Reviewed-by: Steven Holte <holte@chromium.org>
Commit-Queue: Robert Ogden <robertogden@chromium.org>
Cr-Commit-Position: refs/heads/master@{#731853}

chrome/browser/page_load_metrics/observers/previews_ukm_observer.cc

@@ -118,11 +118,6 @@ PreviewsUKMObserver::OnCommit(content::NavigationHandle* navigation_handle,
   if (previews_user_data->cache_control_no_transform_directive()) {
     origin_opt_out_occurred_ = true;
   }
-  if (previews_user_data->server_lite_page_info()) {
-    navigation_restart_penalty_ =
-        navigation_handle->NavigationStart() -
-        previews_user_data->server_lite_page_info()->original_navigation_start;
-  }
 
   lite_page_eligibility_reason_ =
       previews_user_data->EligibilityReasonForPreview(
@@ -202,13 +197,10 @@ void PreviewsUKMObserver::RecordPreviewsTypes() {
       page_load_metrics::PageEndReason::PAGE_END_REASON_COUNT);
 
   // Only record previews types when they are active.
-  // |navigation_restart_penalty_| is included here because a Lite Page Redirect
-  // preview can be attempted and not commit. This incurs the penalty but may
-  // also cause no preview to be committed.
   if (!lite_page_seen_ && !noscript_seen_ && !resource_loading_hints_seen_ &&
       !defer_all_script_seen_ && !offline_preview_seen_ &&
       !origin_opt_out_occurred_ && !save_data_enabled_ &&
-      !lite_page_redirect_seen_ && !navigation_restart_penalty_.has_value()) {
+      !lite_page_redirect_seen_) {
     return;
   }
 
@@ -235,10 +227,6 @@ void PreviewsUKMObserver::RecordPreviewsTypes() {
     builder.Setsave_data_enabled(1);
   if (previews_likely_)
     builder.Setpreviews_likely(1);
-  if (navigation_restart_penalty_.has_value()) {
-    builder.Setnavigation_restart_penalty(
-        navigation_restart_penalty_->InMilliseconds());
-  }
 
   if (ShouldOptionalEligibilityReasonBeRecorded(
           lite_page_eligibility_reason_)) {

chrome/browser/page_load_metrics/observers/previews_ukm_observer.h

@@ -82,7 +82,6 @@ class PreviewsUKMObserver : public page_load_metrics::PageLoadMetricsObserver {
       defer_all_script_eligibility_reason_;
   base::Optional<previews::PreviewsEligibilityReason>
       offline_eligibility_reason_;
-  base::Optional<base::TimeDelta> navigation_restart_penalty_;
 
   SEQUENCE_CHECKER(sequence_checker_);
 

chrome/browser/previews/previews_content_util.cc

@@ -201,9 +201,6 @@ CreateServerLitePageInfoFromNavigationHandle(
   if (!navigation_handle->GetWebContents())
     return nullptr;
 
-  server_lite_page_info->original_navigation_start =
-      navigation_handle->NavigationStart();
-
   const net::HttpRequestHeaders& headers =
       navigation_handle->GetRequestHeaders();
 

chrome/browser/previews/previews_lite_page_redirect_url_loader_interceptor.cc

@@ -237,7 +237,6 @@ PreviewsLitePageRedirectURLLoaderInterceptor::GetOrCreateServerLitePageInfo(
 
   previews::PreviewsUserData::ServerLitePageInfo* info =
       previews_data->server_lite_page_info();
-  info->original_navigation_start = navigation_handle->NavigationStart();
   if (session_id.has_value())
     info->drp_session_key = session_id.value();
 

components/previews/content/previews_user_data.h

@@ -31,10 +31,6 @@ class PreviewsUserData {
       return std::make_unique<ServerLitePageInfo>(*this);
     }
 
-    // The start time of the original navigation, that is, the one started by
-    // the user.
-    base::TimeTicks original_navigation_start = base::TimeTicks();
-
     // The page id used for this preview.
     uint64_t page_id = 0;
 

components/previews/content/previews_user_data_unittest.cc

@@ -47,8 +47,6 @@ TEST(PreviewsUserDataTest, DeepCopy) {
   EXPECT_FALSE(data->offline_preview_used());
   EXPECT_EQ(data->server_lite_page_info(), nullptr);
 
-  base::TimeTicks now = base::TimeTicks::Now();
-
   data->set_data_savings_inflation_percent(123);
   data->set_cache_control_no_transform_directive();
   data->SetCommittedPreviewsType(previews::PreviewsType::NOSCRIPT);
@@ -56,7 +54,6 @@ TEST(PreviewsUserDataTest, DeepCopy) {
   data->set_black_listed_for_lite_page(true);
   data->set_server_lite_page_info(
       std::make_unique<PreviewsUserData::ServerLitePageInfo>());
-  data->server_lite_page_info()->original_navigation_start = now;
 
   PreviewsUserData data_copy(*data);
   EXPECT_EQ(id, data_copy.page_id());
@@ -68,7 +65,6 @@ TEST(PreviewsUserDataTest, DeepCopy) {
   EXPECT_TRUE(data_copy.black_listed_for_lite_page());
   EXPECT_TRUE(data_copy.offline_preview_used());
   EXPECT_NE(data->server_lite_page_info(), nullptr);
-  EXPECT_EQ(data->server_lite_page_info()->original_navigation_start, now);
 }
 
 TEST(PreviewsUserDataTest, TestCoinFlip_HasCommittedPreviewsType) {

tools/metrics/ukm/ukm.xml

@@ -7670,6 +7670,9 @@ be describing additional metrics about the same event.
     </summary>
   </metric>
   <metric name="navigation_restart_penalty">
+    <obsolete>
+      Feature removed in M79.
+    </obsolete>
     <summary>
       Set to the number of milliseconds spent restarting navigations when a Lite
       Page Redirect preview is attempted, whether or not it is committed, during