Update from https://crrev.com/333737

base/prefs/json_pref_store.cc

Index: base/prefs/json_pref_store.cc
diff --git a/base/prefs/json_pref_store.cc b/base/prefs/json_pref_store.cc
index da545b8634cfd1aff408204fe1638043a6ee57cc..c2ff42593fad0eef46fa7fdba82c6546905d5055 100644
--- a/base/prefs/json_pref_store.cc
+++ b/base/prefs/json_pref_store.cc
@@ -303,13 +303,17 @@ void JsonPrefStore::CommitPendingWrite() {
 
   // Schedule a write for any lossy writes that are outstanding to ensure that
   // they get flushed when this function is called.
-  if (pending_lossy_write_)
-    writer_.ScheduleWrite(this);
+  SchedulePendingLossyWrites();
 
   if (writer_.HasPendingWrite() && !read_only_)
     writer_.DoScheduledWrite();
 }
 
+void JsonPrefStore::SchedulePendingLossyWrites() {
+  if (pending_lossy_write_)
+    writer_.ScheduleWrite(this);
+}
+
 void JsonPrefStore::ReportValueChanged(const std::string& key, uint32 flags) {
   DCHECK(CalledOnValidThread());