Supervised users: Add histogram to record filtering results

chrome/browser/supervised_user/supervised_user_url_filter.cc

Index: chrome/browser/supervised_user/supervised_user_url_filter.cc
diff --git a/chrome/browser/supervised_user/supervised_user_url_filter.cc b/chrome/browser/supervised_user/supervised_user_url_filter.cc
index 5305ee2940f5dcd8b396c2656fdfeeccb9b5783d..b08be1233ed1e5443eba2f6bd1b73ae9975e1c7c 100644
--- a/chrome/browser/supervised_user/supervised_user_url_filter.cc
+++ b/chrome/browser/supervised_user/supervised_user_url_filter.cc
@@ -10,7 +10,6 @@
 #include "base/containers/hash_tables.h"
 #include "base/files/file_path.h"
 #include "base/json/json_file_value_serializer.h"
-#include "base/metrics/histogram.h"
 #include "base/sha1.h"
 #include "base/strings/string_number_conversions.h"
 #include "base/strings/string_util.h"
@@ -417,16 +416,12 @@ void SupervisedUserURLFilter::SetManualHosts(
     const std::map<std::string, bool>* host_map) {
   DCHECK(CalledOnValidThread());
   host_map_ = *host_map;
-  UMA_HISTOGRAM_CUSTOM_COUNTS("ManagedMode.ManualHostsEntries",
-                              host_map->size(), 1, 1000, 50);
 }
 
 void SupervisedUserURLFilter::SetManualURLs(
     const std::map<GURL, bool>* url_map) {
   DCHECK(CalledOnValidThread());
   url_map_ = *url_map;
-  UMA_HISTOGRAM_CUSTOM_COUNTS("ManagedMode.ManualURLsEntries",
-                              url_map->size(), 1, 1000, 50);
 }
 
 void SupervisedUserURLFilter::InitAsyncURLChecker(