Audio Player: Update Polymer to the latest version (0.3.4)

ui/file_manager/file_manager/audio_player.html

Index: ui/file_manager/file_manager/audio_player.html
diff --git a/ui/file_manager/file_manager/audio_player.html b/ui/file_manager/file_manager/audio_player.html
index c7a044b19cc9546b9e3e7009e9a548d4b5d5a8a7..1f9fa2c536c693f16a9d39532890dae615e60a3e 100644
--- a/ui/file_manager/file_manager/audio_player.html
+++ b/ui/file_manager/file_manager/audio_player.html
@@ -26,8 +26,8 @@
     <script src="../../../../ui/webui/resources/js/cr/ui/array_data_model.js">
     </script>
 
-    <script src="../../../../third_party/polymer_legacy/platform/platform.js"></script>
-    <script src="../../../../third_party/polymer_legacy/polymer/polymer.js"></script>
+    <script src="../../../../third_party/polymer/platform/platform.js"></script>
+    <script src="../../../../third_party/polymer/polymer/polymer.js"></script>
 
     <script src="common/js/async_util.js"></script>
     <script src="common/js/util.js"></script>
@@ -186,7 +186,7 @@
 
   <!-- Definition of <audio-player> tag. -->
   <polymer-element name="audio-player"
-                   attributes="tracks playing currenttrackurl playcount">
+                   attributes="playing currenttrackurl playcount">
     <template>
       <link rel="stylesheet"
             href="audio_player/elements/audio_player.css"></link>