Add note about using escape character when serializing JSON

Author: ecfan

articles/logic-apps/workflow-definition-language-functions-reference.md

@@ -4895,8 +4895,9 @@ For this example, both expressions find nodes that match the `<location></locati
 > [!NOTE]
 >
 > If you're working in code view, escape the double quotation mark (") by using the backslash character (\\). 
-> If you're working in the expression editor, you don't need to escape the double quotation mark because the 
-> backslash character is added automatically, for example:
+> For example, you need to use escape characters when you serialize an expression as a JSON string. 
+> However, if you're working in the Logic App Designer or expression editor, you don't need to escape the 
+> double quotation mark because the backslash character is added automatically to the underlying definition, for example:
 > 
 > * Code view: `xpath(xml(body('Http')), '/*[name()=\"file\"]/*[name()=\"location\"]')`
 >