Make sure that the builder includes the search app crx in the installer.

build/common.gypi

 # Copyright (c) 2011 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.
 
 # IMPORTANT:
 # Please don't directly include this file if you are building via gyp_chromium,
 # since gyp_chromium is automatically forcing its inclusion.
 {
   # Variables expected to be overriden on the GYP command line (-D) or by
   # ~/.gyp/include.gypi.
@@ skipping 853 matching lines @@
 
       ['asan==1', {
         'clang%': 1,
         # Do not use Chrome plugins for Clang. The Clang version in
         # third_party/asan may be different from the default one.
         'clang_use_chrome_plugins%': 0,
       }],
     ],
     # List of default apps to install in new profiles.  The first list contains
     # the source files as found in svn.  The second list, used only for linux,
-    # contains the destination location for each of the files.
+    # contains the destination location for each of the files.  When a crx
+    # is added or removed from the list, the chrome/browser/resources/
+    # default_apps/external_extensions.json file must also be updated.
     'default_apps_list': [
       'browser/resources/default_apps/external_extensions.json',
       'browser/resources/default_apps/gmail.crx',
+      'browser/resources/default_apps/search.crx',
       'browser/resources/default_apps/youtube.crx',
     ],
     'default_apps_list_linux_dest': [
       '<(PRODUCT_DIR)/default_apps/external_extensions.json',
       '<(PRODUCT_DIR)/default_apps/gmail.crx',
+      '<(PRODUCT_DIR)/default_apps/search.crx',
       '<(PRODUCT_DIR)/default_apps/youtube.crx',
     ],
   },
   'target_defaults': {
     'variables': {
       # The condition that operates on chromium_code is in a target_conditions
       # section, and will not have access to the default fallback value of
       # chromium_code at the top of this file, or to the chromium_code
       # variable placed at the root variables scope of .gyp files, because
       # those variables are not set at target scope.  As a workaround,
@@ skipping 1691 matching lines @@
     # settings in target dicts.  SYMROOT is a special case, because many other
     # Xcode variables depend on it, including variables such as
     # PROJECT_DERIVED_FILE_DIR.  When a source group corresponding to something
     # like PROJECT_DERIVED_FILE_DIR is added to a project, in order for the
     # files to appear (when present) in the UI as actual files and not red
     # red "missing file" proxies, the correct path to PROJECT_DERIVED_FILE_DIR,
     # and therefore SYMROOT, needs to be set at the project level.
     'SYMROOT': '<(DEPTH)/xcodebuild',
   },
 }