Adding documentation for extensions options pages.

chrome/common/extensions/docs/static/options.html

+<div id="pageData-title" class="pageData">Options</div>
+<div id="pageData-showTOC" class="pageData">true</div>
+<p>To allow users to customize the behavior of your extension, you may wish to provide an options page. If you do, a link to it will be provided from the Extensions Management page at chrome://extensions. Clicking on this link will open a new tab pointing at your options page.
+
+<h2>Step 1: Declare your options page in the manifest</h2>
+
+<pre>{
+  "name": "Test Extension",
+  "version": "1.0",
+  "description": "This is a test",
+  <b>"options_page": "options.html"</b>
+}
+</pre>
+
+
+<h2>Step 2: Write your options page</h2>
+
+Here is an example options page:
+
+<pre>
+&lt;html>
+&lt;head>&lt;title>My Test Extension Options&lt;/title>&lt;/head>
+&lt;script type="text/javascript">
+
+// Saves options to localStorage.
+function save_options() {
+  var select = document.getElementById("color");
+  var color = select.children[select.selectedIndex].value;
+  localStorage["favorite_color"] = color;
+
+  // Update status to let user know options were saved.
+  var status = document.getElementById("status");
+  status.innerHTML = "Options Saved.";
+  setTimeout(function() {
+    status.innerHTML = "";
+  }, 750);
+}
+
+// Restores select box state to saved value from localStorage.
+function restore_options() {
+  var favorite = localStorage["favorite_color"];
+  if (!favorite) {
+    return;
+  }
+  var select = document.getElementById("color");
+  for (var i = 0; i &lt; select.children.length; i++) {
+    var child = select.children[i];
+    if (child.value == favorite) {
+      child.selected = "true";
+      break;
+    }
+  }
+}
+
+&lt;/script>
+
+&lt;body onload="restore_options()">
+
+Favorite Color:
+&lt;select id="color">
+ &lt;option value="red">red&lt;/option>
+ &lt;option value="green">green&lt;/option>
+ &lt;option value="blue">blue&lt;/option>
+ &lt;option value="yellow">yellow&lt;/option>
+&lt;/select>
+
+&lt;br>
+&lt;button onclick="save_options()">Save&lt;/button>
+&lt;/body>
+&lt;/html>
+</pre>
+
+<h2>Important Notes</h2>
+<ul>
+<li>This feature is checked in to the trunk and should land in official builds sometime <b>after</b> version 4.0.222.x.</li>
+<li>We plan on providing some default css styles to encourage a consistent look across different extensions' options pages. You can star <a href="http://crbug.com/25317">crbug.com/25317</a> to be notified of updates.</li>
+</ul>