Do not typedef ExtensionId/ID, since it's already available in extension_id.h

chrome/browser/extensions/api/image_writer_private/operation_manager.h

Index: chrome/browser/extensions/api/image_writer_private/operation_manager.h
diff --git a/chrome/browser/extensions/api/image_writer_private/operation_manager.h b/chrome/browser/extensions/api/image_writer_private/operation_manager.h
index 60d25a6760f5145f45531e78cbeb39ad2a26c50f..993019bdc67431f06cb60f6a9455151e5d6b7176 100644
--- a/chrome/browser/extensions/api/image_writer_private/operation_manager.h
+++ b/chrome/browser/extensions/api/image_writer_private/operation_manager.h
@@ -19,6 +19,7 @@
 #include "content/public/browser/notification_registrar.h"
 #include "extensions/browser/browser_context_keyed_api_factory.h"
 #include "extensions/browser/extension_registry_observer.h"
+#include "extensions/common/extension_id.h"
 #include "url/gurl.h"
 
 namespace image_writer_api = extensions::api::image_writer_private;
@@ -43,8 +44,6 @@ class OperationManager : public BrowserContextKeyedAPI,
                          public extensions::ExtensionRegistryObserver,
                          public base::SupportsWeakPtr<OperationManager> {
  public:
-  typedef std::string ExtensionId;
-
   explicit OperationManager(content::BrowserContext* context);
   ~OperationManager() override;