add textbox::content_origin

include/nana/gui/widgets/skeletons/text_editor.hpp

@@ -86,6 +86,7 @@ namespace nana{	namespace widgets
 			~text_editor();
 
 			size caret_size() const;
+			const point& content_origin() const;
 
 			void set_highlight(const ::std::string& name, const ::nana::color&, const ::nana::color&);
 			void erase_highlight(const ::std::string& name);

include/nana/gui/widgets/textbox.hpp

@@ -140,6 +140,8 @@ namespace nana
 
 		colored_area_access_interface* colored_area_access();
 
+		point content_origin() const;
+
 		/// Enables/disables the textbox to indent a line. Idents a new line when it is created by pressing enter.
 		/// @param generator generates text for identing a line. If it is empty, textbox indents the line according to last line.
 		textbox& indention(bool, std::function<std::string()> generator = {});