choose src over currentsrc

lib/single-file/doc-helper.js

@@ -258,7 +258,7 @@ this.docHelper = this.docHelper || (() => {
 						naturalHeight: naturalHeight,
 						width: imageElement.width,
 						height: imageElement.height,
-						src: (!imageElement.currentSrc.startsWith("data:") && imageElement.currentSrc) || (!imageElement.src.startsWith("data:") && imageElement.src)
+						src: (!imageElement.src.startsWith("data:") && imageElement.src) || (!imageElement.currentSrc.startsWith("data:") && imageElement.currentSrc)
 					};
 				}
 				data.push(imageData);