paper: make actual changeset entries have backgrounds on /graph

This patch removes a separate container for backgrounds only and puts
backgrounds on changeset elements themselves. This makes it so that JS code
doesn't need to create background elements separately anymore.

There's a bit of manipulating positions of elements: every changeset entry has
a "fg" element that gets a higher z-index than <canvas> element. This
prioritizes text information, so that even if it somehow gets close to the
graph drawn on <canvas> (which has z-index of 5), it'll still be on top of it.
This can happen if commit message has a long first line and browser window is
narrow, for example.

mercurial/templates/paper/graph.tmpl

@@ -50,21 +50,14
 <noscript><p>The revision graph only works with JavaScript-enabled browsers.</p></noscript>
 
 <div id="wrapper">
-<ul id="nodebgs" class="stripes2"></ul>
 <canvas id="graph"></canvas>
-<ul id="graphnodes">{nodes%graphentry}</ul>
+<ul id="graphnodes" class="stripes2">{nodes%graphentry}</ul>
 </div>
 
 <script type="text/javascript"{if(nonce, ' nonce="{nonce}"')}>
 var data = {jsdata|json};
 var graph = new Graph();
 graph.scale({bg_height});
-
-graph.vertex = function(x, y, radius, color, parity, cur) \{
-	Graph.prototype.vertex.apply(this, arguments);
-	return ['<li class="bg"></li>', ''];
-}
-
 graph.render(data);
 </script>
 

mercurial/templates/paper/graphentry.tmpl

@@ -1,7 +1,9
 <li data-node="{node|short}">
+ <div class="fg">
  <span class="desc">
   <a href="{url|urlescape}rev/{node|short}{sessionvars%urlparameter}">{desc|strip|firstline|escape|nonempty}</a>
  </span>
  {alltags}
  <div class="info"><span class="age">{date|rfc822date}</span>, by {author|person}</div>
+ </div>
 </li>

mercurial/templates/static/style-paper.css

@@ -460,22 +460,19 canvas {
 }
 
 ul#graphnodes {
-	position: absolute;
-	z-index: 10;
-	top: -1.0em;
-	list-style: none inside none;
-	padding: 0;
-}
-
-ul#nodebgs {
 	list-style: none inside none;
 	padding: 0;
 	margin: 0;
-	top: -0.7em;
 }
 
-ul#graphnodes li, ul#nodebgs li {
+ul#graphnodes li {
 	height: 39px;
+	overflow: visible;
+}
+
+ul#graphnodes li .fg {
+	position: absolute;
+	z-index: 10;
 }
 
 ul#graphnodes li .info {

tests/test-hgweb-empty.t

@@ -294,21 +294,14 Some tests for hgweb in an empty reposit
   <noscript><p>The revision graph only works with JavaScript-enabled browsers.</p></noscript>
   
   <div id="wrapper">
-  <ul id="nodebgs" class="stripes2"></ul>
   <canvas id="graph"></canvas>
-  <ul id="graphnodes"></ul>
+  <ul id="graphnodes" class="stripes2"></ul>
   </div>
   
   <script type="text/javascript">
   var data = [];
   var graph = new Graph();
   graph.scale(39);
-  
-  graph.vertex = function(x, y, radius, color, parity, cur) {
-  	Graph.prototype.vertex.apply(this, arguments);
-  	return ['<li class="bg"></li>', ''];
-  }
-  
   graph.render(data);
   </script>