Windows Integration: Don't use size_t in StringUtil, it's unsigned

shell_integration/windows/OCUtil/StringUtil.cpp

@@ -17,19 +17,19 @@
 
 #include "StringUtil.h"
 
-std::string StringUtil::toUtf8(const wchar_t *utf16, size_t len)
+std::string StringUtil::toUtf8(const wchar_t *utf16, int len)
 {
 	if (len < 0) {
-		len = wcslen(utf16);
+		len = (int) wcslen(utf16);
 	}
     std::wstring_convert<std::codecvt_utf8_utf16<wchar_t> > converter;
     return converter.to_bytes(utf16, utf16+len);
 }
 
-std::wstring StringUtil::toUtf16(const char *utf8, size_t len)
+std::wstring StringUtil::toUtf16(const char *utf8, int len)
 {
 	if (len < 0) {
-		len = strlen(utf8);
+		len = (int) strlen(utf8);
 	}
 	std::wstring_convert<std::codecvt_utf8_utf16<wchar_t> > converter;
     return converter.from_bytes(utf8, utf8+len);

shell_integration/windows/OCUtil/StringUtil.h

@@ -20,8 +20,8 @@
 
 class __declspec(dllexport) StringUtil {
 public:
-	static std::string  toUtf8(const wchar_t* utf16, size_t len = -1);
-	static std::wstring toUtf16(const char* utf8, size_t len = -1);
+	static std::string  toUtf8(const wchar_t* utf16, int len = -1);
+	static std::wstring toUtf16(const char* utf8, int len = -1);
 
 	template<class T>
 	static bool begins_with(const T& input, const T& match)