Copy resources refered to in the HTML to the output folder

lib/src/dependency_graph.dart

 // Copyright (c) 2015, 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.
 
 /// Tracks the shape of the import/export graph and dependencies between files.
 library dev_compiler.src.dependency_graph;
 
 import 'dart:collection' show HashSet;
 
 import 'package:analyzer/analyzer.dart' show parseDirectives;
@@ skipping 55 matching lines @@
   /// Node associated with a resolved [uri].
   SourceNode nodeFromUri(Uri uri) {
     var uriString = Uri.encodeFull('$uri');
     return nodes.putIfAbsent(uri, () {
       var source = _context.sourceFactory.forUri(uriString);
       var extension = path.extension(uriString);
       if (extension == '.html') {
         return new HtmlSourceNode(uri, source, this);
       } else if (extension == '.dart' || uriString.startsWith('dart:')) {
         return new DartSourceNode(uri, source);
-      } else if (extension == '.js' || extension == '.css') {
+      } else {
         return new ResourceSourceNode(uri, source);
-      } else {
-        assert(false); // unreachable
       }
     });
   }
 }
 
 /// A node in the import graph representing a source file.
 abstract class SourceNode {
   /// Resolved URI for this node.
   final Uri uri;
 
@@ skipping 48 matching lines @@
 }
 
 /// A node representing an entry HTML source file.
 class HtmlSourceNode extends SourceNode {
   /// Resources included by default on any application.
   final runtimeDeps;
 
   /// Libraries referred to via script tags.
   Set<DartSourceNode> scripts = new Set<DartSourceNode>();
 
+  /// Link-rel stylesheets and images.
+  Set<ResourceSourceNode> resources = new Set<ResourceSourceNode>();
+
   @override
-  Iterable<SourceNode> get allDeps => [scripts, runtimeDeps].expand((e) => e);
+  Iterable<SourceNode> get allDeps =>
+      [scripts, resources, runtimeDeps].expand((e) => e);
 
   @override
   Iterable<SourceNode> get depsWithoutParts => allDeps;
 
   /// Parsed document, updated whenever [update] is invoked.
   Document document;
 
   HtmlSourceNode(Uri uri, Source source, SourceGraph graph)
       : runtimeDeps = graph.runtimeDeps,
         super(uri, source);
@@ skipping 17 matching lines @@
         if (node == null || !node.source.exists()) {
           _reportError(graph, 'Script file $src not found', script);
         }
         if (node != null) newScripts.add(node);
       }
 
       if (!_same(newScripts, scripts)) {
         structureChanged = true;
         scripts = newScripts;
       }
+
+      var newResources = new Set<ResourceSourceNode>();
+      for (var tag in document.querySelectorAll('link[rel="stylesheet"]')) {
+        newResources
+            .add(graph.nodeFromUri(uri.resolve(tag.attributes['href'])));
+      }
+      for (var tag in document.querySelectorAll('img')) {
+        newResources.add(graph.nodeFromUri(uri.resolve(tag.attributes['src'])));
+      }
+      if (!_same(newResources, resources)) {
+        structureChanged = true;
+        resources = newResources;
+      }
     }
   }
 
   void _reportError(SourceGraph graph, String message, Node node) {
     graph._reporter.enterHtml(source.uri);
     graph._reporter.log(new DependencyGraphError(message, node.sourceSpan));
     graph._reporter.leaveHtml();
   }
 }
 
@@ skipping 254 matching lines @@
   'harmony_feature_check.js',
   'dart_runtime.js',
   'dart_core.js'
 ];
 
 /// Runtime files added to applications when running in server mode.
 final runtimeFilesForServerMode = new List<String>.from(defaultRuntimeFiles)
   ..addAll(const ['messages_widget.js', 'messages.css']);
 
 final _log = new Logger('dev_compiler.dependency_graph');