Windows build fix.

file/dialog.cpp

@@ -8,18 +8,18 @@
 // For desktop operating systems only. Stubbed out on Android.
 // Simplified as this will only be used in utilities / temp code.
 // An false returned means cancel;
-bool OpenFileDialog(const char *title, const char *extension, std::string *filename)
+bool OpenFileDialog(const wchar_t *title, const wchar_t *extension, std::wstring *filename)
 {
 	OPENFILENAME of;
 	memset(&of, 0, sizeof(of));
-	char buffer[512] = {0};
+	wchar_t buffer[512] = {0};
 	of.lStructSize = sizeof(OPENFILENAME);
 	of.hInstance = 0;
 	of.hwndOwner = GetActiveWindow();
 
 	// These weird strings with zeroes in them can't be dealt with using normal string
 	// functions, so here we go - evil hackery.
-	char filter[256] = "XXX files\0*.XXX\0\0";
+	wchar_t filter[256] = L"XXX files\0*.XXX\0\0";
 	memcpy(filter, extension, 3);
 	memcpy(filter + 12, extension, 3);
 	of.lpstrFilter = filter;
@@ -34,18 +34,18 @@ bool OpenFileDialog(const char *title, const char *extension, std::string *filen
 	return true;
 }
 
-bool SaveFileDialog(const char *title, const char *extension, std::string *filename)
+bool SaveFileDialog(const wchar_t *title, const wchar_t *extension, std::wstring *filename)
 {
 	OPENFILENAME of;
 	memset(&of, 0, sizeof(of));
-	char buffer[512] = {0};
+	wchar_t buffer[512] = {0};
 	of.lStructSize = sizeof(OPENFILENAME);
 	of.hInstance = 0;
 	of.hwndOwner = GetActiveWindow();
 
 	// These weird strings with zeroes in them can't be dealt with using normal string
 	// functions, so here we go - evil hackery.
-	char filter[256] = "XXX files\0*.XXX\0\0";
+	wchar_t filter[256] = L"XXX files\0*.XXX\0\0";
 	memcpy(filter, extension, 3);
 	memcpy(filter + 12, extension, 3);
 	of.lpstrFilter = filter;