Fix review comments: https://github.com/mdn/webextensions-examples/issues/30#issuecomment-172649839

* added README
* moved listeners above addListener calls

notify-link-clicks-i18n/README.md

@@ -0,0 +1,25 @@
+# notify-link-clicks-i18n
+
+## What it does
+
+This extension includes:
+
+* a content script, "content-script.js", that is injected into all pages
+* a background script, "background-script.js"
+
+The content script listens for clicks in the page it's attached to.
+If a click is on a link, the content script sends the link's href
+to the background script.
+
+The background script listens for this message. When the background script
+receives the message, it displays a notification containing the href.
+
+The notification's content, as well as the extension's name and description, are
+localized into German and Dutch, as well as en-US.
+
+# What it shows
+
+* how to inject content scripts declaratively using manifest.json
+* how to send messages from a content script to a background script
+* how to display system notifications using the notifications API
+* how to use the internationalization (i18n) system

notify-link-clicks-i18n/background-script.js

@@ -1,8 +1,3 @@
-/*
-Assign `notify()` as a listener to messages from the content script.
-*/
-chrome.runtime.onMessage.addListener(notify);
-
 /*
 Log that we received the message.
 Then display a notification. The notification contains the URL,
@@ -19,3 +14,8 @@ function notify(message) {
     "message": content
   });
 }
+
+/*
+Assign `notify()` as a listener to messages from the content script.
+*/
+chrome.runtime.onMessage.addListener(notify);

notify-link-clicks-i18n/content-script.js

@@ -1,8 +1,3 @@
-/*
-Add notifyExtension() as a listener to click events.
-*/
-window.addEventListener("click", notifyExtension);
-
 /*
 If the click was on a link, send a message to the background page.
 The message contains the link's URL.
@@ -18,3 +13,8 @@ function notifyExtension(e) {
   console.log("content script sending message");
   chrome.runtime.sendMessage({"url": target.href});
 }
+
+/*
+Add notifyExtension() as a listener to click events.
+*/
+window.addEventListener("click", notifyExtension);