Code Cleanup (#3178)

Noticed an unused variable in the image parser, from before a old refactor.

core/modules/parsers/imageparser.js

@@ -17,8 +17,7 @@ var ImageParser = function(type,text,options) {
 			type: "element",
 			tag: "img",
 			attributes: {}
-		},
-		src;
+		};
 	if(options._canonical_uri) {
 		element.attributes.src = {type: "string", value: options._canonical_uri};
 	} else if(text) {