Run clang-modernize -use-nullptr over src/extensions/.

extensions/browser/value_store/leveldb_value_store.cc

Index: extensions/browser/value_store/leveldb_value_store.cc
diff --git a/extensions/browser/value_store/leveldb_value_store.cc b/extensions/browser/value_store/leveldb_value_store.cc
index 58cf32fecf5083cf9d4340f54487fe7476243e92..a3ffeee1f39cc4f1aeb0c80fccc8be369f209478 100644
--- a/extensions/browser/value_store/leveldb_value_store.cc
+++ b/extensions/browser/value_store/leveldb_value_store.cc
@@ -237,7 +237,7 @@ ValueStore::WriteResult LeveldbValueStore::Remove(
       return MakeWriteResult(read_error.Pass());
 
     if (old_value) {
-      changes->push_back(ValueStoreChange(*it, old_value.release(), NULL));
+      changes->push_back(ValueStoreChange(*it, old_value.release(), nullptr));
       batch.Delete(*it);
     }
   }
@@ -263,7 +263,7 @@ ValueStore::WriteResult LeveldbValueStore::Clear() {
     scoped_ptr<base::Value> next_value;
     whole_db.RemoveWithoutPathExpansion(next_key, &next_value);
     changes->push_back(
-        ValueStoreChange(next_key, next_value.release(), NULL));
+        ValueStoreChange(next_key, next_value.release(), nullptr));
   }
 
   DeleteDbFile();
@@ -329,7 +329,7 @@ scoped_ptr<ValueStore::Error> LeveldbValueStore::EnsureDbIsOpen() {
   options.max_open_files = 0;  // Use minimum.
   options.create_if_missing = true;
 
-  leveldb::DB* db = NULL;
+  leveldb::DB* db = nullptr;
   leveldb::Status status =
       leveldb::DB::Open(options, db_path_.AsUTF8Unsafe(), &db);
   if (!status.ok())