Retrofit devices do not do allocatable space / 2.

Retrofit devices have two supers, so the allocatable
space does not need to be halved.

Test: manual OTA
Bug: 118506262
Change-Id: I31c77b9318e7c0b6bc6d1a8ae6efa70a3383b05f
diff --git a/mock_dynamic_partition_control.h b/mock_dynamic_partition_control.h
index 7b37581..24aca06 100644
--- a/mock_dynamic_partition_control.h
+++ b/mock_dynamic_partition_control.h
@@ -47,6 +47,7 @@
                     uint32_t));
   MOCK_METHOD1(GetDeviceDir, bool(std::string*));
   MOCK_METHOD0(IsDynamicPartitionsEnabled, bool());
+  MOCK_METHOD0(IsDynamicPartitionsRetrofit, bool());
 };
 
 }  // namespace chromeos_update_engine