Convert //content/renderer from scoped_ptr to std::unique_ptr

content/renderer/dom_automation_controller.cc

Index: content/renderer/dom_automation_controller.cc
diff --git a/content/renderer/dom_automation_controller.cc b/content/renderer/dom_automation_controller.cc
index 4087458301a2ed5b3615bac3e2b3e0c6b6b1f96b..3f119b6920d14f9590b722226bdfe2ea665f8bfc 100644
--- a/content/renderer/dom_automation_controller.cc
+++ b/content/renderer/dom_automation_controller.cc
@@ -90,7 +90,7 @@ bool DomAutomationController::SendMsg(const gin::Arguments& args) {
 
   std::string json;
   JSONStringValueSerializer serializer(&json);
-  scoped_ptr<base::Value> value;
+  std::unique_ptr<base::Value> value;
 
   // Warning: note that JSON officially requires the root-level object to be
   // an object (e.g. {foo:3}) or an array, while here we're serializing