Add field trial param to suppress disallowed subresource notifications.

components/subresource_filter/core/browser/subresource_filter_features.cc

Index: components/subresource_filter/core/browser/subresource_filter_features.cc
diff --git a/components/subresource_filter/core/browser/subresource_filter_features.cc b/components/subresource_filter/core/browser/subresource_filter_features.cc
index d9374e15e7770c78c06dba3ce67c227c2e6eeb71..9d319f36006434df524704cb009c344fca01275a 100644
--- a/components/subresource_filter/core/browser/subresource_filter_features.cc
+++ b/components/subresource_filter/core/browser/subresource_filter_features.cc
@@ -6,6 +6,7 @@
 
 #include <string>
 
+#include "base/metrics/field_trial_params.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_split.h"
 #include "base/strings/string_util.h"
@@ -35,6 +36,8 @@ const char kActivationListPhishingInterstitial[] = "phishing_interstitial";
 const char kPerformanceMeasurementRateParameterName[] =
     "performance_measurement_rate";
 
+const char kSuppressNotificationsParameterName[] = "suppress_notifications";
+
 ActivationLevel GetMaximumActivationLevel() {
   std::string activation_level = variations::GetVariationParamValueByFeature(
       kSafeBrowsingSubresourceFilter, kActivationLevelParameterName);
@@ -84,4 +87,10 @@ double GetPerformanceMeasurementRate() {
   return value < 1 ? value : 1;
 }
 
+bool ShouldSuppressNotifications() {
+  return base::GetFieldTrialParamByFeatureAsBool(
+      kSafeBrowsingSubresourceFilter, kSuppressNotificationsParameterName,
+      false /* default value */);
+}
+
 }  // namespace subresource_filter