TINY-969: extract width/height in more generic way
TINY-969: extract width/height in more generic way

tinymce/tinymce,MediehusetTek/tinymce,TeamupCom/tinymce,FernCreek/tinymce,tinymce/tinymce,danielpunkass/tinymce,adaptiffdesigns/tinymce,tinymce/tinymce,danielpunkass/tinymce,leofeyer/tinymce,danielpunkass/tinymce,FernCreek/tinymce,gencer/tinymce,FernCreek/tinymce,TeamupCom/tinymce,adaptiffdesigns/tinymce,gencer/tinymce,MediehusetTek/tinymce,leofeyer/tinymce