TextEditor: Hide LineNumberFilter implementation

One of the two non-standard items exposed in the TextEditorPlugin class
interface.

Change-Id: I89755c6a2b168f31b69d3904d6d043273b462ea6
Reviewed-by: David Schulz <david.schulz@qt.io>

src/plugins/texteditor/texteditorplugin.cpp

@@ -99,7 +99,6 @@ public:
     FilePath m_marginActionFileName;
 
     TextEditorSettings settings;
-    LineNumberFilter lineNumberFilter; // Goto line functionality for quick open
     OutlineFactory outlineFactory;
 
     FindInFiles findInFilesFilter;
@@ -426,11 +425,6 @@ void TextEditorPlugin::extensionsInitialized()
                                });
 }
 
-LineNumberFilter *TextEditorPlugin::lineNumberFilter()
-{
-    return &m_instance->d->lineNumberFilter;
-}
-
 ExtensionSystem::IPlugin::ShutdownFlag TextEditorPlugin::aboutToShutdown()
 {
     Highlighter::handleShutdown();