Add support for custom subresource filter InstallerAttributes.

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 9d319f36006434df524704cb009c344fca01275a..f14186953a366b1ecda7f97be4391175e948e319 100644
--- a/components/subresource_filter/core/browser/subresource_filter_features.cc
+++ b/components/subresource_filter/core/browser/subresource_filter_features.cc
@@ -33,6 +33,8 @@ const char kActivationListSocialEngineeringAdsInterstitial[] =
     "social_engineering_ads_interstitial";
 const char kActivationListPhishingInterstitial[] = "phishing_interstitial";
 
+const char kRulesetFlavorParameterName[] = "ruleset_flavor";
+
 const char kPerformanceMeasurementRateParameterName[] =
     "performance_measurement_rate";
 
@@ -93,4 +95,10 @@ bool ShouldSuppressNotifications() {
       false /* default value */);
 }
 
+std::string GetRulesetFlavor() {
+  return variations::GetVariationParamValueByFeature(
+      subresource_filter::kSafeBrowsingSubresourceFilter,
+      subresource_filter::kRulesetFlavorParameterName);
+}
+
 }  // namespace subresource_filter