Allow app banners to trigger on 0 engagement.

chrome/browser/banners/app_banner_settings_helper.cc

 // Copyright 2014 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/banners/app_banner_settings_helper.h"
 
 #include <stddef.h>
 
 #include <algorithm>
 #include <string>
@@ skipping 129 matching lines @@
 // Queries variations for the maximum site engagement score required to trigger
 // the banner showing.
 void UpdateSiteEngagementToTrigger() {
   std::string total_param = variations::GetVariationParamValue(
       kBannerParamsKey, kBannerParamsEngagementTotalKey);
 
   if (!total_param.empty()) {
     double total_engagement = -1;
 
     if (base::StringToDouble(total_param, &total_engagement) &&
-        total_engagement > 0) {
+        total_engagement >= 0) {
       AppBannerSettingsHelper::SetTotalEngagementToTrigger(total_engagement);
     }
   }
 }
 
 // Queries variations for updates to the default engagement values assigned
 // to direct and indirect navigations.
 void UpdateEngagementWeights() {
   std::string direct_param = variations::GetVariationParamValue(
       kBannerParamsKey, kBannerParamsDirectKey);
@@ skipping 488 matching lines @@
     return true;
   }
 
   // Assume any value which is not "0" or "false" indicates that we should use
   // site engagement.
   std::string param = variations::GetVariationParamValue(
       kBannerParamsKey, kBannerSiteEngagementParamsKey);
 
   return (!param.empty() && param != "0" && param != "false");
 }