Rename the app banner variations key for total site engagement score.

chrome/browser/banners/app_banner_settings_helper.cc

Index: chrome/browser/banners/app_banner_settings_helper.cc
diff --git a/chrome/browser/banners/app_banner_settings_helper.cc b/chrome/browser/banners/app_banner_settings_helper.cc
index 864b46a4297cfd902ea6811a27c9d5c3f9f2669b..820ad3a9c112aa092d10db1c7c95e8b87d28c6a7 100644
--- a/chrome/browser/banners/app_banner_settings_helper.cc
+++ b/chrome/browser/banners/app_banner_settings_helper.cc
@@ -78,6 +78,7 @@ const char kBannerParamsDirectKey[] = "direct";
 const char kBannerParamsIndirectKey[] = "indirect";
 const char kBannerParamsTotalKey[] = "total";
 const char kBannerParamsMinutesKey[] = "minutes";
+const char kBannerParamsEngagementTotalKey[] = "site_engagement_total";
 const char kBannerSiteEngagementParamsKey[] = "use_site_engagement";
 
 // Engagement weight assigned to direct and indirect navigations.
@@ -139,7 +140,7 @@ double GetEventEngagement(ui::PageTransition transition_type) {
 // the banner showing.
 void UpdateSiteEngagementToTrigger() {
   std::string total_param = variations::GetVariationParamValue(
-      kBannerParamsKey, kBannerParamsTotalKey);
+      kBannerParamsKey, kBannerParamsEngagementTotalKey);
 
   if (!total_param.empty()) {
     double total_engagement = -1;