moved variable declaration

lib/browser-polyfill/chrome-browser-polyfill.js

@@ -26,9 +26,8 @@
 
 	const FEATURE_TESTS = {};
 
-	let nativeAPI;
 	if (isChrome && !this.browser) {
-		nativeAPI = this.chrome;
+		const nativeAPI = this.chrome;
 		this.__defineGetter__("browser", () => ({
 			browserAction: {
 				onClicked: {