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

extensions/common/manifest_handler.cc

Index: extensions/common/manifest_handler.cc
diff --git a/extensions/common/manifest_handler.cc b/extensions/common/manifest_handler.cc
index 78df1cd1cdf99a10a4a2a55b4905020457d4c247..042f714a5c659518ae108e3e39c259b43f313be5 100644
--- a/extensions/common/manifest_handler.cc
+++ b/extensions/common/manifest_handler.cc
@@ -18,7 +18,7 @@ namespace {
 
 static base::LazyInstance<ManifestHandlerRegistry> g_registry =
     LAZY_INSTANCE_INITIALIZER;
-static ManifestHandlerRegistry* g_registry_override = NULL;
+static ManifestHandlerRegistry* g_registry_override = nullptr;
 
 ManifestHandlerRegistry* GetRegistry() {
   if (!g_registry_override)
@@ -60,12 +60,12 @@ void ManifestHandler::Register() {
 }
 
 ManifestPermission* ManifestHandler::CreatePermission() {
-  return NULL;
+  return nullptr;
 }
 
 ManifestPermission* ManifestHandler::CreateInitialRequiredPermission(
     const Extension* extension) {
-  return NULL;
+  return nullptr;
 }
 
 // static
@@ -172,7 +172,7 @@ ManifestPermission* ManifestHandlerRegistry::CreatePermission(
     const std::string& name) {
   ManifestHandlerMap::const_iterator it = handlers_.find(name);
   if (it == handlers_.end())
-    return NULL;
+    return nullptr;
 
   return it->second->CreatePermission();
 }
@@ -196,7 +196,7 @@ ManifestHandlerRegistry* ManifestHandlerRegistry::SetForTesting(
   if (new_registry != g_registry.Pointer())
     g_registry_override = new_registry;
   else
-    g_registry_override = NULL;
+    g_registry_override = nullptr;
   return old_registry;
 }