Remove unused DRP code for migrating prefs

components/data_reduction_proxy/core/browser/data_reduction_proxy_service.cc

Index: components/data_reduction_proxy/core/browser/data_reduction_proxy_service.cc
diff --git a/components/data_reduction_proxy/core/browser/data_reduction_proxy_service.cc b/components/data_reduction_proxy/core/browser/data_reduction_proxy_service.cc
index 86374060dd21a9c9eed9ec5cc3643d5a93d02ede..957de50677f2f013dd69cd9a378c9a2f23d48b12 100644
--- a/components/data_reduction_proxy/core/browser/data_reduction_proxy_service.cc
+++ b/components/data_reduction_proxy/core/browser/data_reduction_proxy_service.cc
@@ -90,18 +90,6 @@ void DataReductionProxyService::Shutdown() {
   weak_factory_.InvalidateWeakPtrs();
 }
 
-void DataReductionProxyService::EnableCompressionStatisticsLogging(
-    PrefService* prefs,
-    const scoped_refptr<base::SequencedTaskRunner>& ui_task_runner,
-    const base::TimeDelta& commit_delay) {
-  DCHECK(CalledOnValidThread());
-  DCHECK(!compression_stats_);
-  DCHECK(!prefs_);
-  prefs_ = prefs;
-  compression_stats_.reset(
-      new DataReductionProxyCompressionStats(this, prefs_, commit_delay));
-}
-
 void DataReductionProxyService::UpdateContentLengths(
     int64_t data_used,
     int64_t original_size,