TextEditor: Use new setup pattern for the finders

The FindInFiles definition cannot go yet to the .cpp yet as there
are some exported functions.

Change-Id: I2d2f02ae80b560e3147f461fcbee0fa62b8085a3
Reviewed-by: David Schulz <david.schulz@qt.io>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>

src/plugins/texteditor/texteditorplugin.cpp

@@ -67,10 +67,6 @@ const char kCurrentDocumentWordUnderCursor[] = "CurrentDocument:WordUnderCursor"
 class TextEditorPluginPrivate : public QObject
 {
 public:
-    FindInFiles findInFilesFilter;
-    FindInCurrentFile findInCurrentFileFilter;
-    FindInOpenFiles findInOpenFilesFilter;
-
     MarkdownEditorFactory markdownEditorFactory;
     JsonEditorFactory jsonEditorFactory;
 };
@@ -122,6 +118,10 @@ void TextEditorPlugin::initialize()
     setupBookmarkView();
     setupBookmarkFilter();
 
+    setupFindInFiles(this);
+    setupFindInCurrentFile();
+    setupFindInOpenFiles();
+
     d = new TextEditorPluginPrivate;
 
     Context context(TextEditor::Constants::C_TEXTEDITOR);