Move getProp and setProp to common.js

public/js/reader.js

@@ -61,28 +61,6 @@ const updateMode = (mode, targetPage) => {
 	});
 };
 
-/**
- * Set an alpine.js property
- *
- * @function setProp
- * @param {string} key - Key of the data property
- * @param {*} prop - The data property
- */
-const setProp = (key, prop) => {
-	$('#root').get(0).__x.$data[key] = prop;
-};
-
-/**
- * Get an alpine.js property
- *
- * @function getProp
- * @param {string} key - Key of the data property
- * @return {*} The data property
- */
-const getProp = (key) => {
-	return $('#root').get(0).__x.$data[key];
-};
-
 /**
  * Get dimension of the pages in the entry from the API and update the view
  */