EditorManager: Small API clean-up

- Move private enum to private header
- Add missing parameter to openEditorAtSearchResult
- Remove convenience singular close* methods, we have {} nowadays

Change-Id: Ic5b6d831a9f506ffee09b89b3358874433d62998
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/git/gitplugin.cpp

@@ -1405,7 +1405,7 @@ void GitPluginPrivate::commitFromEditor()
     // Close the submit editor
     m_submitActionTriggered = true;
     QTC_ASSERT(submitEditor(), return);
-    EditorManager::closeDocument(submitEditor()->document());
+    EditorManager::closeDocuments({submitEditor()->document()});
 }
 
 bool GitPluginPrivate::submitEditorAboutToClose()