Remove base::Value::CreateNullValue

cc/benchmarks/invalidation_benchmark.cc

Index: cc/benchmarks/invalidation_benchmark.cc
diff --git a/cc/benchmarks/invalidation_benchmark.cc b/cc/benchmarks/invalidation_benchmark.cc
index 89f5973feb9f69f67c14ad20f479a6780b07c662..6a61522ceb01b251e8e5e6f57727a17b95eecba0 100644
--- a/cc/benchmarks/invalidation_benchmark.cc
+++ b/cc/benchmarks/invalidation_benchmark.cc
@@ -9,6 +9,7 @@
 #include <algorithm>
 #include <limits>
 
+#include "base/memory/ptr_util.h"
 #include "base/rand_util.h"
 #include "base/values.h"
 #include "cc/layers/layer.h"
@@ -123,7 +124,7 @@ bool InvalidationBenchmark::ProcessMessage(std::unique_ptr<base::Value> value) {
   if (message->HasKey("notify_done")) {
     message->GetBoolean("notify_done", &notify_done);
     if (notify_done)
-      NotifyDone(base::Value::CreateNullValue());
+      NotifyDone(base::MakeUnique<base::Value>());
     return true;
   }
   return false;