Build ChromeVox using gyp.

chrome/browser/resources/chromeos/chromevox/compress_js.gypi

+# Copyright 2014 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.
+
+# Include this file in a target to produce a bundled and compressed
+# JavaScript file from a set of files with closure-style dependency
+# declarations.  The following variables must be defined before including
+# this file:
+# js_root_flags: List of '-r' flags to jsbundler.py for locating the
+#   .js files.
+# output_file: path of the compressed JavaScript bundle.
+#
+# In addition, the target must have a 'sources' list containing the
+# top-level files for the bundle.
+
+{
+  'actions': [
+    {
+      'action_name': 'js_compress',
+      'message': 'Compress js for <(_target_name)',
+      'variables': {
+        'js_files': [
+          '<!@(python tools/jsbundler.py <(js_root_flags) <(_sources))'
+        ],
+      },
+      'inputs': [
+        'tools/jsbundler.py',
+        '<@(js_files)',
+      ],
+      'outputs': [
+        '<(output_file)'
+      ],
+      'action': [
+        'python',
+        'tools/jsbundler.py',
+        '-m', 'compressed_bundle',
+        '-o', '<(output_file)',
+        '<@(js_files)',
+      ],
+    },
+  ],
+}