QSaveFile[win]: store error in nativeRenameOverwrite

We want to drop the fallback path, so we need to set an appropriate
error when the native rename fails.

Change-Id: I2746d79b9e5666f54c35ff7ac29a74191cf22740
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>

src/corelib/io/qfsfileengine_win.cpp

@@ -419,10 +419,10 @@ bool QFSFileEnginePrivate::nativeRenameOverwrite(const QString &newName)
 
     bool res = SetFileInformationByHandle(fileHandle, FileRenameInfo, renameInfo,
                                           DWORD(renameDataSize));
-#if 0
-    if (!res)
-        qErrnoWarning("QFSFileEnginePrivate::nativeRenameOverwrite failed");
-#endif
+    if (!res) {
+        DWORD error = GetLastError();
+        q_func()->setError(QFile::RenameError, qt_error_string(int(error)));
+    }
     return res;
 }