urlmon/tests: Fix a test failure on Vista and higher.

dlls/urlmon/tests/protocol.c

@@ -1854,7 +1854,9 @@ static void test_gopher_protocol(void)
     trace("Testing gopher protocol...\n");
 
     hres = CoGetClassObject(&CLSID_GopherProtocol, CLSCTX_INPROC_SERVER, NULL, &IID_IUnknown, (void**)&unk);
-    ok(hres == S_OK, "CoGetClassObject failed: %08x\n", hres);
+    ok(hres == S_OK ||
+       hres == REGDB_E_CLASSNOTREG, /* Gopher protocol has been removed as of Vista */
+       "CoGetClassObject failed: %08x\n", hres);
     if(FAILED(hres))
         return;