layers: Switch CV over to layer object types

Convert internal uses of VkDebugReportObjectTypeEXT for the core-
validation layer to use the internal layer-povided object-type.

Also modified tests for changed error text.

Change-Id: If080f4bf452ead0c6fecc648309bfd95b27fc0ce
diff --git a/layers/descriptor_sets.h b/layers/descriptor_sets.h
index 0e8cdb5..de47dc9 100644
--- a/layers/descriptor_sets.h
+++ b/layers/descriptor_sets.h
@@ -50,6 +50,7 @@
 #include "vk_layer_utils.h"
 #include "vk_safe_struct.h"
 #include "vulkan/vk_layer.h"
+#include "vk_object_types.h"
 #include <map>
 #include <memory>
 #include <unordered_map>