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

extensions/common/manifest_handlers/background_info.cc

Index: extensions/common/manifest_handlers/background_info.cc
diff --git a/extensions/common/manifest_handlers/background_info.cc b/extensions/common/manifest_handlers/background_info.cc
index 230eba13745a4a55ff76581869e8e83cf58f729f..f3bb99a1d6383dca2c7b9268b64c69d3d9cf0fd2 100644
--- a/extensions/common/manifest_handlers/background_info.cc
+++ b/extensions/common/manifest_handlers/background_info.cc
@@ -117,7 +117,7 @@ bool BackgroundInfo::Parse(const Extension* extension, base::string16* error) {
 bool BackgroundInfo::LoadBackgroundScripts(const Extension* extension,
                                            const std::string& key,
                                            base::string16* error) {
-  const base::Value* background_scripts_value = NULL;
+  const base::Value* background_scripts_value = nullptr;
   if (!extension->manifest()->Get(key, &background_scripts_value))
     return true;
 
@@ -127,7 +127,7 @@ bool BackgroundInfo::LoadBackgroundScripts(const Extension* extension,
     return false;
   }
 
-  const base::ListValue* background_scripts = NULL;
+  const base::ListValue* background_scripts = nullptr;
   background_scripts_value->GetAsList(&background_scripts);
   for (size_t i = 0; i < background_scripts->GetSize(); ++i) {
     std::string script;
@@ -145,7 +145,7 @@ bool BackgroundInfo::LoadBackgroundScripts(const Extension* extension,
 bool BackgroundInfo::LoadBackgroundPage(const Extension* extension,
                                         const std::string& key,
                                         base::string16* error) {
-  const base::Value* background_page_value = NULL;
+  const base::Value* background_page_value = nullptr;
   if (!extension->manifest()->Get(key, &background_page_value))
     return true;
 
@@ -204,7 +204,7 @@ bool BackgroundInfo::LoadBackgroundPersistent(const Extension* extension,
     return true;
   }
 
-  const base::Value* background_persistent = NULL;
+  const base::Value* background_persistent = nullptr;
   if (!extension->manifest()->Get(keys::kBackgroundPersistent,
                                   &background_persistent))
     return true;
@@ -224,7 +224,7 @@ bool BackgroundInfo::LoadBackgroundPersistent(const Extension* extension,
 
 bool BackgroundInfo::LoadAllowJSAccess(const Extension* extension,
                                        base::string16* error) {
-  const base::Value* allow_js_access = NULL;
+  const base::Value* allow_js_access = nullptr;
   if (!extension->manifest()->Get(keys::kBackgroundAllowJsAccess,
                                   &allow_js_access))
     return true;