Add a forgotten ChromeVox test to the build system.

chrome/browser/resources/chromeos/chromevox/chromevox_tests.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.
 
 {
   'includes': [
     '../../../../js_unittest_vars.gypi',
   ],
   'variables': {
     'chromevox_test_deps_js_file': '<(SHARED_INTERMEDIATE_DIR)/chrome/browser/resources/chromeos/chromevox/test_deps.js',
@@ skipping 109 matching lines @@
         '<(DEPTH)/chrome/test/base/test_chrome_web_ui_controller_factory.h',
         '<(DEPTH)/chrome/test/base/web_ui_browser_test.cc',
         '<(DEPTH)/chrome/test/base/web_ui_browser_test.h',
         '<(DEPTH)/chrome/browser/extensions/browsertest_util.cc',
         '<(DEPTH)/chrome/browser/extensions/browsertest_util.h',
 
         'common/aria_util_test.unitjs',
         'common/braille_text_handler_test.unitjs',
         'common/braille_util_test.unitjs',
         'common/command_store_test.unitjs',
+        'common/content_editable_extractor_test.unitjs',
         'common/cursor_selection_test.unitjs',
         'common/dom_util_test.unitjs',
         'common/editable_text_area_shadow_test.unitjs',
         'common/editable_text_test.unitjs',
         'common/find_util_test.unitjs',
         'common/key_sequence_test.unitjs',
         'common/math_semantic_tree_test.unitjs',
         'common/page_selection_test.unitjs',
         'common/selection_util_test.unitjs',
         'common/spannable_test.unitjs',
@@ skipping 63 matching lines @@
             '<@(js_files)',
           ],
         },
       ],
       'dependencies': [
         'chromevox_test_messages_js',
       ],
     },  # target chromevox_test_deps_js
   ],
 }