Use sequenced workers for the getting the system's font list.

content/common/font_list.cc

Index: content/common/font_list.cc
diff --git a/chrome/test/data/extensions/platform_apps/web_view/media_access/deny/test.js b/content/common/font_list.cc
similarity index 56%
copy from chrome/test/data/extensions/platform_apps/web_view/media_access/deny/test.js
copy to content/common/font_list.cc
index 1886432c3055a84510594bb8c7e0d3ac28feb045..398ee80cf60525da22e5f6339360722920d1836c 100644
--- a/chrome/test/data/extensions/platform_apps/web_view/media_access/deny/test.js
+++ b/content/common/font_list.cc
@@ -2,6 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-chrome.app.runtime.onLaunched.addListener(function() {
-  chrome.app.window.create('embedder.html', {}, function () {});
-});

[falken, 2013/04/03 09:24:35]

content/common/font_list.cc is a new file. Rietveld just thinks it's a modified
copy of
chrome/test/data/extensions/platform_apps/web_view/media_access/deny/test.js

+#include "content/common/font_list.h"
+
+namespace content {
+const char kFontListSequenceToken[] = "_font_list_sequence_token_";
+}