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

extensions/browser/api/storage/settings_test_util.cc

Index: extensions/browser/api/storage/settings_test_util.cc
diff --git a/extensions/browser/api/storage/settings_test_util.cc b/extensions/browser/api/storage/settings_test_util.cc
index b5142f0889c9f80ec21ef70818ffdf5fa14f73fb..3623e2602a685b626c0bddec7bd03719eab4baac 100644
--- a/extensions/browser/api/storage/settings_test_util.cc
+++ b/extensions/browser/api/storage/settings_test_util.cc
@@ -42,7 +42,7 @@ static void AssignStorage(ValueStore** dst, ValueStore* src) {
 ValueStore* GetStorage(scoped_refptr<const Extension> extension,
                        settings_namespace::Namespace settings_namespace,
                        StorageFrontend* frontend) {
-  ValueStore* storage = NULL;
+  ValueStore* storage = nullptr;
   frontend->RunWithStorage(
       extension, settings_namespace, base::Bind(&AssignStorage, &storage));
   base::MessageLoop::current()->RunUntilIdle();
@@ -135,7 +135,7 @@ KeyedService* MockExtensionSystemWithEventRouter::Build(
 
 EventRouter* MockExtensionSystemWithEventRouter::event_router() {
   if (!event_router_.get())
-    event_router_.reset(new EventRouter(browser_context(), NULL));
+    event_router_.reset(new EventRouter(browser_context(), nullptr));
   return event_router_.get();
 }