Fix undefined enums

There are a few places where an enum value is purpoposly getting a value
that is not one of the enum values. This is causing a problem when
testing. I have a quick fix to make those values `int` instead of the
enum type.

The variables could contain `-1` as a special value to indicate that no
storage class or builtin is used. We cannot change the enum class to add
`-1` because it is defined in spirv headers.

common/output_stream.cpp

@@ -204,7 +204,7 @@ std::string ToStringShaderStage(SpvReflectShaderStageFlagBits stage) {
   return "???";
 }
 
-std::string ToStringSpvStorageClass(SpvStorageClass storage_class) {
+std::string ToStringSpvStorageClass(int storage_class) {
   switch (storage_class) {
     case SpvStorageClassUniformConstant:
       return "UniformConstant";
@@ -343,7 +343,7 @@ std::string ToStringDescriptorType(SpvReflectDescriptorType value) {
   return "VK_DESCRIPTOR_TYPE_???";
 }
 
-static std::string ToStringSpvBuiltIn(SpvBuiltIn built_in) {
+static std::string ToStringSpvBuiltIn(int built_in) {
   switch (built_in) {
     case SpvBuiltInPosition:
       return "Position";

common/output_stream.h

@@ -9,7 +9,7 @@
 
 std::string ToStringSpvSourceLanguage(SpvSourceLanguage lang);
 std::string ToStringSpvExecutionModel(SpvExecutionModel model);
-std::string ToStringSpvStorageClass(SpvStorageClass storage_class);
+std::string ToStringSpvStorageClass(int storage_class);
 std::string ToStringSpvDim(SpvDim dim);
 std::string ToStringSpvBuiltIn(const SpvReflectInterfaceVariable& variable, bool preface);
 std::string ToStringSpvImageFormat(SpvImageFormat fmt);
@@ -66,4 +66,4 @@ class SpvReflectToYaml {
   std::map<const SpvReflectInterfaceVariable*, uint32_t> interface_variable_to_index_;
 };
 
-#endif
+#endif

spirv_reflect.h

@@ -393,7 +393,7 @@ typedef struct SpvReflectTypeDescription {
   const char*                       type_name;
   // Non-NULL if type is member of a struct
   const char*                       struct_member_name;
-  SpvStorageClass                   storage_class;
+  int                               storage_class;
   SpvReflectTypeFlags               type_flags;
   SpvReflectDecorationFlags         decoration_flags;
 
@@ -429,7 +429,7 @@ typedef struct SpvReflectInterfaceVariable {
   SpvStorageClass                     storage_class;
   const char*                         semantic;
   SpvReflectDecorationFlags           decoration_flags;
-  SpvBuiltIn                          built_in;
+  int                                 built_in;
   SpvReflectNumericTraits             numeric;
   SpvReflectArrayTraits               array;