Remove base::StringValue

extensions/browser/api/idle/idle_manager.h

Index: extensions/browser/api/idle/idle_manager.h
diff --git a/extensions/browser/api/idle/idle_manager.h b/extensions/browser/api/idle/idle_manager.h
index 2dd296b4f354b26e7fec7c19be44c5274e3a8d61..e4a076b2c41c79ffdc15fd29a75d403255c1de38 100644
--- a/extensions/browser/api/idle/idle_manager.h
+++ b/extensions/browser/api/idle/idle_manager.h
@@ -23,7 +23,6 @@
 
 namespace base {
 class Value;
-using StringValue = Value;
 }  // namespace base
 
 namespace content {
@@ -92,8 +91,7 @@ class IdleManager : public ExtensionRegistryObserver,
 
   void QueryState(int threshold, const QueryStateCallback& notify);
   void SetThreshold(const std::string& extension_id, int threshold);
-  static std::unique_ptr<base::StringValue> CreateIdleValue(
-      ui::IdleState idle_state);
+  static std::unique_ptr<base::Value> CreateIdleValue(ui::IdleState idle_state);
 
   // Override default event class. Callee assumes ownership. Used for testing.
   void SetEventDelegateForTest(std::unique_ptr<EventDelegate> event_delegate);