Data Reduction Proxy: Remove duplicate functions

components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc
index 16cf8fef44f2434bf99a14bdce28e3029f2d733c..9e81bc06d11b888b978da2d19eb1a70df83d7d84 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_config.cc
@@ -454,7 +454,7 @@ void DataReductionProxyConfig::ReloadConfig() {
   DCHECK(thread_checker_.CalledOnValidThread());
   DCHECK(configurator_);
 
-  if (enabled_by_user_ && !config_values_->holdback() &&
+  if (enabled_by_user_ && !params::IsIncludedInHoldbackFieldTrial() &&
       !config_values_->proxies_for_http().empty()) {
     configurator_->Enable(!secure_proxy_allowed_ || is_captive_portal_,
                           config_values_->proxies_for_http());
@@ -736,12 +736,6 @@ bool DataReductionProxyConfig::ContainsDataReductionProxy(
   return false;
 }
 
-// Returns true if the Data Reduction Proxy promo may be shown. This is not
-// tied to whether the Data Reduction Proxy is enabled.
-bool DataReductionProxyConfig::promo_allowed() const {
-  return config_values_->promo_allowed();
-}
-
 void DataReductionProxyConfig::SetProxyConfig(bool enabled, bool at_startup) {
   DCHECK(thread_checker_.CalledOnValidThread());
   enabled_by_user_ = enabled;