Support different types in the parameter store

The test framework stores size_t and int32_t values in the parameter store
by converting them all to int. This is ok in practice, since we assume int
covers int32_t and we don't have test data larger than 2GB. But it's
confusing and error-prone. So make the parameter store a union, which allows
size_t values not to be potentially truncated and makes the code a little
clearer.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
diff --git a/visualc/VS2010/mbedTLS.vcxproj b/visualc/VS2010/mbedTLS.vcxproj
index b6df742..c75b353 100644
--- a/visualc/VS2010/mbedTLS.vcxproj
+++ b/visualc/VS2010/mbedTLS.vcxproj
@@ -237,6 +237,7 @@
     <ClInclude Include="..\..\include\psa\crypto_struct.h" />

     <ClInclude Include="..\..\include\psa\crypto_types.h" />

     <ClInclude Include="..\..\include\psa\crypto_values.h" />

+    <ClInclude Include="..\..\tests\include\test\arguments.h" />

     <ClInclude Include="..\..\tests\include\test\asn1_helpers.h" />

     <ClInclude Include="..\..\tests\include\test\constant_flow.h" />

     <ClInclude Include="..\..\tests\include\test\fake_external_rng_for_test.h" />