Do not use QDir::separator() for internal paths

Internal paths are supposed to be normalized

Change-Id: Ic6943ce13ad389dfdb44054a9e6f03da8c6cd88d
Reviewed-by: Eike Ziller <eike.ziller@theqtcompany.com>

src/plugins/coreplugin/documentmanager.cpp

@@ -746,7 +746,7 @@ QString DocumentManager::getSaveAsFileName(const IDocument *document, const QStr
     }
 
     absoluteFilePath = getSaveFileName(tr("Save File As"),
-        path + QDir::separator() + fileName,
+        path + QLatin1Char('/') + fileName,
         filterString,
         selectedFilter);
     return absoluteFilePath;