Refactor emitter in web-ui to make dart.js the last script, also cleanup tests

lib/src/emitters.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /** Collects several code emitters for the template tool. */
 library emitters;
 
 import 'package:csslib/parser.dart' as css;
 import 'package:csslib/visitor.dart';
 import 'package:html5lib/dom.dart';
@@ skipping 836 matching lines @@
   }
 
   var expr = 'new autogenerated.$constructor';
   var varName = '__html${statics.declarations.length}';
   statics.add('final', varName, node.sourceSpan, expr);
   return '${varName}.clone(true)';
 }
 
 /** Trim down the html for the main html page. */
 void transformMainHtml(Document document, FileInfo fileInfo,
-    PathMapper pathMapper, bool hasCss, bool rewriteUrls, Messages messages) {
+    PathMapper pathMapper, bool hasCss, bool rewriteUrls, Messages messages,
+    String bootstrapOutName) {
   var filePath = fileInfo.inputUrl.resolvedPath;
 
-  bool dartLoaderFound = false;
+  var dartLoaderTag = null;
   for (var tag in document.queryAll('script')) {
     var src = tag.attributes['src'];
     if (src != null && src.split('/').last == 'dart.js') {
-      dartLoaderFound = true;
+      dartLoaderTag = tag;
     }
     if (tag.attributes['type'] == 'application/dart') {
       tag.remove();
     } else if (src != null && rewriteUrls) {
       tag.attributes["src"] = pathMapper.transformUrl(filePath, src);
     }
   }
   for (var tag in document.queryAll('link')) {
     var href = tag.attributes['href'];
     var rel = tag.attributes['rel'];
@@ skipping 27 matching lines @@
     for (var i = styles.length - 1; i > 0 ; i--) {
       styles[i].remove();
     }
   }
 
   // TODO(jmesserly): put this in the global CSS file?
   // http://dvcs.w3.org/hg/webcomponents/raw-file/tip/spec/templates/index.html#css-additions
   document.head.nodes.insert(0, parseFragment(
       '<style>template { display: none; }</style>'));
 
-  if (!dartLoaderFound) {
+
+  var bootstrapScript = parseFragment(
+        '<script type="application/dart" src="$bootstrapOutName"></script>');
+  if (dartLoaderTag == null) {
+    document.body.nodes.add(bootstrapScript);
     document.body.nodes.add(parseFragment(
         '<script type="text/javascript" src="packages/browser/dart.js">'
         '</script>\n'));
+  } else if (dartLoaderTag.parent != document.body) {
+    document.body.nodes.add(bootstrapScript);
+  } else {
+    document.body.nodes.insertBefore(bootstrapScript, dartLoaderTag);
   }
 
   // Insert the "auto-generated" comment after the doctype, otherwise IE will
   // go into quirks mode.
   int commentIndex = 0;
   DocumentType doctype = find(document.nodes, (n) => n is DocumentType);
   if (doctype != null) {
     commentIndex = document.nodes.indexOf(doctype) + 1;
     // TODO(jmesserly): the html5lib parser emits a warning for missing
     // doctype, but it allows you to put it after comments. Presumably they do
@@ skipping 17 matching lines @@
   return """
 // Auto-generated from $filename.
 // DO NOT EDIT.
 $lib
 import 'dart:html' as autogenerated;
 import 'dart:svg' as autogenerated_svg;
 import 'package:web_ui/web_ui.dart' as autogenerated;
 import 'package:web_ui/observe/observable.dart' as __observe;
 """;
 }