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

extensions/common/permissions/media_galleries_permission_data.cc

Index: extensions/common/permissions/media_galleries_permission_data.cc
diff --git a/extensions/common/permissions/media_galleries_permission_data.cc b/extensions/common/permissions/media_galleries_permission_data.cc
index 495c1f917ebe1f95ca12e791c4e93d03fd3f0b03..13f7d93d38c736d37db697ed34baf6f95c1e0026 100644
--- a/extensions/common/permissions/media_galleries_permission_data.cc
+++ b/extensions/common/permissions/media_galleries_permission_data.cc
@@ -23,8 +23,8 @@ bool MediaGalleriesPermissionData::Check(
   return permission_ == specific_param.permission;
 }
 
-scoped_ptr<base::Value> MediaGalleriesPermissionData::ToValue() const {
-  return scoped_ptr<base::Value>(new base::StringValue(permission_));
+std::unique_ptr<base::Value> MediaGalleriesPermissionData::ToValue() const {
+  return std::unique_ptr<base::Value>(new base::StringValue(permission_));
 }
 
 bool MediaGalleriesPermissionData::FromValue(const base::Value* value) {