don't pass an array to processStylesheet

lib/single-file/single-file-core.js

@@ -1218,7 +1218,7 @@ this.SingleFileCore = this.SingleFileCore || (() => {
 					} else if (ruleData.type == "Atrule" && ruleData.name == "charset") {
 						removedRules.push(cssRule);
 					} else if (ruleData.type == "Atrule" && (ruleData.name == "media" || ruleData.name == "supports")) {
-						promises.push(this.processStylesheet(ruleData.block.children.toArray(), baseURI, options, cssVariables, batchRequest));
+						promises.push(this.processStylesheet(ruleData.block.children, baseURI, options, cssVariables, batchRequest));
 					} else if (ruleData.type == "Atrule" && ruleData.name == "font-face") {
 						promises.push(processFontFaceRule(ruleData));
 					}