Convert //extensions/{common,shell} from scoped_ptr to std::unique_ptr

extensions/shell/browser/shell_prefs.h

Index: extensions/shell/browser/shell_prefs.h
diff --git a/extensions/shell/browser/shell_prefs.h b/extensions/shell/browser/shell_prefs.h
index 1e94c0e6bad8ec80e1e1effc441f3f0a90dc44e0..5cc02bf94c560cbdad1508863569ce224b1379f7 100644
--- a/extensions/shell/browser/shell_prefs.h
+++ b/extensions/shell/browser/shell_prefs.h
@@ -5,7 +5,7 @@
 #ifndef EXTENSIONS_SHELL_BROWSER_SHELL_PREFS_H_
 #define EXTENSIONS_SHELL_BROWSER_SHELL_PREFS_H_
 
-#include "base/memory/scoped_ptr.h"
+#include <memory>
 
 class PrefService;
 
@@ -23,10 +23,10 @@ namespace extensions {
 namespace shell_prefs {
 
 // Creates a pref service for device-wide preferences stored in |data_dir|.
-scoped_ptr<PrefService> CreateLocalState(const base::FilePath& data_dir);
+std::unique_ptr<PrefService> CreateLocalState(const base::FilePath& data_dir);
 
 // Creates a pref service that loads user preferences for |browser_context|.
-scoped_ptr<PrefService> CreateUserPrefService(
+std::unique_ptr<PrefService> CreateUserPrefService(
     content::BrowserContext* browser_context);
 
 }  // namespace shell_prefs