doc: hide video and share if being served from CN

In the case where requests are coming from mainland China, hide
links to locations that are blocked and functionality that is
not permitted.

Additionally, some very small cleanup of the JS.

This change requires https://go-review.googlesource.com/c/52873

Change-Id: I7fc68748e629dbe5b966d6bf117e7f7b546966eb
Reviewed-on: https://go-review.googlesource.com/52872Reviewed-by: Chris Broadfoot <cbro@golang.org>

doc/root.html

@@ -6,7 +6,9 @@
 <div class="left">
 
 <div id="learn">
+{{if not $.GoogleCN}}
 <a class="popout share">Pop-out</a>
+{{end}}
 <div class="rootHeading">Try Go</div>
 <div class="input">
 <textarea spellcheck="false" class="code">// You can edit this code!
@@ -26,10 +28,10 @@ Hello, 世界
 </div>
 <div class="buttons">
 <a class="run" href="#" title="Run this code [shift-enter]">Run</a>
-{{if $.Share}}
+{{if not $.GoogleCN}}
 <a class="share" href="#" title="Share this code">Share</a>
-{{end}}
 <a class="tour" href="//tour.golang.org/" title="Learn Go from your browser">Tour</a>
+{{end}}
 </div>
 <div class="toys">
 <select>
@@ -68,37 +70,38 @@ Linux, Mac OS X, Windows, and more.
 
 <div style="clear: both"></div>
 
+{{if not $.GoogleCN}}
 <div class="left">
-
-<div id="video">
-<div class="rootHeading">Featured video</div>
-<iframe width="415" height="241" src="//www.youtube.com/embed/ytEkHepK08c" frameborder="0" allowfullscreen></iframe>
+  <div id="video">
+    <div class="rootHeading">Featured video</div>
+    <iframe width="415" height="241" src="//www.youtube.com/embed/ytEkHepK08c" frameborder="0" allowfullscreen></iframe>
+  </div>
 </div>
+{{end}}
 
-</div>
-
-<div class="right">
-
-<div id="blog">
-<div class="rootHeading">Featured articles</div>
-<div class="read"><a href="//blog.golang.org/">Read more</a></div>
-</div>
+ <div {{if not $.GoogleCN}}class="right"{{end}}>
+	<div id="blog">
+		<div class="rootHeading">Featured articles</div>
+		<div class="read"><a href="//blog.golang.org/">Read more</a></div>
+	</div>
+ </div>
 
-</div>
 
 <div style="clear: both;"></div>
 
-<script type="text/javascript">
+<script>
+(function() {
+	'use strict';
 
-function readableTime(t) {
+  function readableTime(t) {
 		var m = ["January", "February", "March", "April", "May", "June", "July",
 			"August", "September", "October", "November", "December"];
 		var p = t.substring(0, t.indexOf("T")).split("-");
 		var d = new Date(p[0], p[1]-1, p[2]);
 		return d.getDate() + " " + m[d.getMonth()] + " " + d.getFullYear();
-}
+	}
 
-function feedLoaded(result) {
+	window.feedLoaded = function(result) {
 		var blog = document.getElementById("blog");
 		var read = blog.getElementsByClassName("read")[0];
 		for (var i = 0; i < result.length && i < 2; i++) {
@@ -117,9 +120,9 @@ function feedLoaded(result) {
 			when.innerHTML = "Published " + readableTime(entry.Time);
 			blog.insertBefore(when, read);
 		}
-}
+	}
 
-window.initFuncs.push(function() {
+	window.initFuncs.push(function() {
 		// Set up playground if enabled.
 		if (window.playground) {
 			window.playground({
@@ -138,7 +141,11 @@ window.initFuncs.push(function() {
 		$('<script/>').attr('text', 'text/javascript')
 			.attr('src', '//blog.golang.org/.json?jsonp=feedLoaded')
 			.appendTo('body');
+	});
 
+	{{if not $.GoogleCN}}
+
+	window.initFuncs.push(function() {
 		// Set the video at random.
 		var videos = [
 			{h: 241, s: "//www.youtube.com/embed/ytEkHepK08c"}, // Tour of Go
@@ -147,6 +154,8 @@ window.initFuncs.push(function() {
 		];
 		var v = videos[Math.floor(Math.random()*videos.length)];
 		$('#video iframe').attr('height', v.h).attr('src', v.s);
-});
+	});
 
+	{{end}}
+})();
 </script>