Implement installation of the Chrome App Host.

chrome/installer/util/installation_state.h

Index: chrome/installer/util/installation_state.h
diff --git a/chrome/installer/util/installation_state.h b/chrome/installer/util/installation_state.h
index bc7e01ac07b5c149aa799eed6f1a8f089e46436b..5d04dfe1c93e31ec3436c63e8d836ea324339012 100644
--- a/chrome/installer/util/installation_state.h
+++ b/chrome/installer/util/installation_state.h
@@ -1,4 +1,4 @@
-// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
@@ -154,6 +154,7 @@ class InstallationState {
     CHROME_BROWSER_INDEX,
     CHROME_FRAME_INDEX,
     CHROME_BINARIES_INDEX,
+    CHROME_APP_HOST_INDEX,
     NUM_PRODUCTS
   };