removed obsolete code

lib/single-file/doc-helper.js

@@ -194,14 +194,10 @@ this.docHelper = this.docHelper || (() => {
 	function getSize(imageElement) {
 		const computedStyle = getComputedStyle(imageElement);
 		let width, height, paddingLeft, paddingRight, paddingTop, paddingBottom;
-		if (computedStyle.getPropertyValue("box-sizing") == "content-box") {
-			paddingLeft = paddingRight = paddingTop = paddingBottom = 0;
-		} else {
-			paddingLeft = getWidth("padding-left", computedStyle);
-			paddingRight = getWidth("padding-right", computedStyle);
-			paddingTop = getWidth("padding-top", computedStyle);
-			paddingBottom = getWidth("padding-bottom", computedStyle);
-		}
+		paddingLeft = getWidth("padding-left", computedStyle);
+		paddingRight = getWidth("padding-right", computedStyle);
+		paddingTop = getWidth("padding-top", computedStyle);
+		paddingBottom = getWidth("padding-bottom", computedStyle);
 		width = imageElement.clientWidth;
 		height = imageElement.clientHeight;
 		if (width >= 0 && height >= 0 && paddingLeft >= 0 && paddingRight >= 0 && paddingTop >= 0 && paddingBottom >= 0) {