Initial editor accessibility.

editor/plugins/script_text_editor.cpp

@@ -1958,7 +1958,7 @@ void ScriptTextEditor::drop_data_fw(const Point2 &p_point, const Variant &p_data
 	Dictionary d = p_data;
 
 	CodeEdit *te = code_editor->get_text_editor();
-	Point2i pos = te->get_line_column_at_pos(p_point);
+	Point2i pos = (p_point == Vector2(INFINITY, INFINITY)) ? Point2i(te->get_caret_line(0), te->get_caret_column(0)) : te->get_line_column_at_pos(p_point);
 	int drop_at_line = pos.y;
 	int drop_at_column = pos.x;
 	int selection_index = te->get_selection_at_line_column(drop_at_line, drop_at_column);