amstream/tests: Simplify refcount check.

dlls/amstream/tests/amstream.c

@@ -29,9 +29,10 @@
 #define EXPECT_REF(obj,ref) _expect_ref((IUnknown*)obj, ref, __LINE__)
 static void _expect_ref(IUnknown* obj, ULONG ref, int line)
 {
-    ULONG rc = IUnknown_AddRef(obj);
-    IUnknown_Release(obj);
-    ok_(__FILE__,line)(rc-1 == ref, "expected refcount %d, got %d\n", ref, rc-1);
+    ULONG rc;
+    IUnknown_AddRef(obj);
+    rc = IUnknown_Release(obj);
+    ok_(__FILE__,line)(rc == ref, "expected refcount %d, got %d\n", ref, rc);
 }
 
 static const WCHAR filenameW[] = {'t','e','s','t','.','a','v','i',0};