Remove kEnableLookalikeNavigationSuggestionUI feature

The feature is fully launched and we now have allowlists pushed by the
component updater. Remove the flag and clean up the tests.

Change-Id: I86a2da492ae09748306f2c68846090cba05bff02
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2253020
Commit-Queue: Mustafa Emre Acer <meacer@chromium.org>
Reviewed-by: Livvie Lin <livvielin@chromium.org>
Reviewed-by: Joe DeBlasio <jdeblasio@chromium.org>
Cr-Commit-Position: refs/heads/master@{#780095}

chrome/browser/lookalikes/lookalike_url_navigation_throttle.cc

@@ -87,8 +87,6 @@ bool IsSafeRedirect(const std::string& matching_domain,
 LookalikeUrlNavigationThrottle::LookalikeUrlNavigationThrottle(
     content::NavigationHandle* navigation_handle)
     : content::NavigationThrottle(navigation_handle),
-      interstitials_enabled_(base::FeatureList::IsEnabled(
-          features::kLookalikeUrlNavigationSuggestionsUI)),
       profile_(Profile::FromBrowserContext(
           navigation_handle->GetWebContents()->GetBrowserContext())) {}
 
@@ -177,11 +175,6 @@ ThrottleCheckResult LookalikeUrlNavigationThrottle::HandleThrottleRequest(
         base::BindOnce(&LookalikeUrlNavigationThrottle::PerformChecksDeferred,
                        weak_factory_.GetWeakPtr(), url, navigated_domain,
                        check_safe_redirect));
-    // If we're not going to show an interstitial, there's no reason to delay
-    // the navigation any further.
-    if (!interstitials_enabled_) {
-      return content::NavigationThrottle::PROCEED;
-    }
     return content::NavigationThrottle::DEFER;
   }
 
@@ -272,10 +265,6 @@ void LookalikeUrlNavigationThrottle::PerformChecksDeferred(
   ThrottleCheckResult result =
       PerformChecks(url, navigated_domain, check_safe_redirect, engaged_sites);
 
-  if (!interstitials_enabled_) {
-    return;
-  }
-
   if (result.action() == content::NavigationThrottle::PROCEED) {
     Resume();
     return;
@@ -327,8 +316,7 @@ ThrottleCheckResult LookalikeUrlNavigationThrottle::PerformChecks(
     return content::NavigationThrottle::PROCEED;
   }
 
-  if (interstitials_enabled_ &&
-      ShouldBlockLookalikeUrlNavigation(match_type, navigated_domain)) {
+  if (ShouldBlockLookalikeUrlNavigation(match_type, navigated_domain)) {
     // matched_domain can be a top domain or an engaged domain. Simply use its
     // eTLD+1 as the suggested domain.
     // 1. If matched_domain is a top domain: Top domain list already contains

chrome/browser/lookalikes/lookalike_url_navigation_throttle.h

@@ -76,8 +76,6 @@ class LookalikeUrlNavigationThrottle : public content::NavigationThrottle {
                                        ukm::SourceId source_id,
                                        LookalikeUrlMatchType match_type);
 
-  bool interstitials_enabled_;
-
   Profile* profile_;
   base::WeakPtrFactory<LookalikeUrlNavigationThrottle> weak_factory_{this};
 };

chrome/browser/reputation/local_heuristics.cc

@@ -55,9 +55,7 @@ bool ShouldTriggerSafetyTipFromLookalike(
   }
 
   // If we're already displaying an interstitial, don't warn again.
-  if (base::FeatureList::IsEnabled(
-          features::kLookalikeUrlNavigationSuggestionsUI) &&
-      ShouldBlockLookalikeUrlNavigation(match_type, navigated_domain)) {
+  if (ShouldBlockLookalikeUrlNavigation(match_type, navigated_domain)) {
     return false;
   }
 
@@ -73,16 +71,14 @@ bool ShouldTriggerSafetyTipFromLookalike(
       return false;
     case LookalikeUrlMatchType::kTargetEmbeddingForSafetyTips:
       return kEnableLookalikeTargetEmbedding.Get();
+    case LookalikeUrlMatchType::kSkeletonMatchTop5k:
+      return kEnableLookalikeTopSites.Get();
     case LookalikeUrlMatchType::kSiteEngagement:
     case LookalikeUrlMatchType::kSkeletonMatchTop500:
       // We should only ever reach these cases when the lookalike interstitial
       // is disabled. Now that interstitial is fully launched, this only happens
       // in tests.
-      DCHECK(!base::FeatureList::IsEnabled(
-          features::kLookalikeUrlNavigationSuggestionsUI));
-      return true;
-    case LookalikeUrlMatchType::kSkeletonMatchTop5k:
-      return kEnableLookalikeTopSites.Get();
+      FALLTHROUGH;
     case LookalikeUrlMatchType::kNone:
       NOTREACHED();
   }

chrome/common/chrome_features.cc

@@ -408,12 +408,6 @@ const base::Feature kHideCorsMitigationListPolicySupport{
 // (formerly DataSaver).
 const base::Feature kLiteVideo{"LiteVideo", base::FEATURE_DISABLED_BY_DEFAULT};
 
-// Enables navigation suggestions UI for lookalike URLs (e.g. internationalized
-// domain names that are visually similar to popular domains or to domains with
-// engagement score, such as googlé.com).
-const base::Feature kLookalikeUrlNavigationSuggestionsUI{
-    "LookalikeUrlNavigationSuggestionsUI", base::FEATURE_ENABLED_BY_DEFAULT};
-
 #if defined(OS_WIN)
 // A feature that controls whether Chrome warns about incompatible applications.
 // This feature requires Windows 10 or higher to work because it depends on

chrome/common/chrome_features.h

@@ -284,9 +284,6 @@ extern const base::Feature kKernelnextVMs;
 COMPONENT_EXPORT(CHROME_FEATURES)
 extern const base::Feature kLiteVideo;
 
-COMPONENT_EXPORT(CHROME_FEATURES)
-extern const base::Feature kLookalikeUrlNavigationSuggestionsUI;
-
 #if defined(OS_MACOSX)
 COMPONENT_EXPORT(CHROME_FEATURES)
 extern const base::Feature kMacFullSizeContentView;