trim selector before parsing it

lib/single-file/css-rules-matcher.js

@@ -106,7 +106,7 @@ this.RulesMatcher = this.RulesMatcher || (() => {
 				if (selectorText) {
 					let selectors;
 					try {
-						selectors = cssWhat.parse(selectorText);
+						selectors = cssWhat.parse(selectorText.trim());
 					} catch (error) {
 						/* ignored */
 					}
@@ -299,7 +299,7 @@ this.RulesMatcher = this.RulesMatcher || (() => {
 	function getFilteredSelector(selector) {
 		let selectors;
 		try {
-			selectors = cssWhat.parse(selector);
+			selectors = cssWhat.parse(selector.trim());
 		} catch (error) {
 			return selector;
 		}