Put the pop-up app launcher behind a compile-time flag, and provide defines.

chrome/chrome_browser_ui.gypi

 # 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.
 
 {
   'targets': [
     {
       'target_name': 'browser_ui',
       'type': 'static_library',
@@ skipping 78 matching lines @@
         'browser/ui/android/tab_contents/chrome_web_contents_view_delegate_android.h',
         'browser/ui/android/tab_model/tab_model.cc',
         'browser/ui/android/tab_model/tab_model.h',
         'browser/ui/android/tab_model/tab_model_list.cc',
         'browser/ui/android/tab_model/tab_model_list.h',
         'browser/ui/android/tab_restore_service_delegate_android.cc',
         'browser/ui/android/window_android_helper.cc',
         'browser/ui/android/window_android_helper.h',
         'browser/ui/app_list/app_list_controller.h',
         'browser/ui/app_list/app_list_controller.cc',
+        'browser/ui/app_list/app_list_view_delegate.cc',
+        'browser/ui/app_list/app_list_view_delegate.h',
+        'browser/ui/app_list/apps_model_builder.cc',
+        'browser/ui/app_list/apps_model_builder.h',
+        'browser/ui/app_list/chrome_app_list_item.h',
+        'browser/ui/app_list/extension_app_item.cc',
+        'browser/ui/app_list/extension_app_item.h',
+        'browser/ui/app_list/search_builder.cc',
+        'browser/ui/app_list/search_builder.h',
         'browser/ui/app_modal_dialogs/app_modal_dialog.cc',
         'browser/ui/app_modal_dialogs/app_modal_dialog.h',
         'browser/ui/app_modal_dialogs/app_modal_dialog_queue.cc',
         'browser/ui/app_modal_dialogs/app_modal_dialog_queue.h',
         'browser/ui/app_modal_dialogs/javascript_app_modal_dialog.cc',
         'browser/ui/app_modal_dialogs/javascript_app_modal_dialog.h',
         'browser/ui/app_modal_dialogs/javascript_dialog_creator.cc',
         'browser/ui/app_modal_dialogs/javascript_dialog_creator.h',
         'browser/ui/app_modal_dialogs/native_app_modal_dialog.h',
         'browser/ui/ash/ash_init.cc',
@@ skipping 2163 matching lines @@
             '../printing/printing.gyp:cups',
           ],
         }],
         ['use_gconf==0', {
           'sources!': [
             'browser/ui/gtk/gconf_titlebar_listener.cc',
             'browser/ui/gtk/gconf_titlebar_listener.h',
           ],
         }],
         ['use_ash==1', {
-          'sources': [
-            'browser/ui/app_list/app_list_view_delegate.cc',
-            'browser/ui/app_list/app_list_view_delegate.h',
-            'browser/ui/app_list/apps_model_builder.cc',
-            'browser/ui/app_list/apps_model_builder.h',
-            'browser/ui/app_list/chrome_app_list_item.h',
-            'browser/ui/app_list/extension_app_item.cc',
-            'browser/ui/app_list/extension_app_item.h',
-            'browser/ui/app_list/search_builder.cc',
-            'browser/ui/app_list/search_builder.h',
-          ],
           'dependencies': [
             '../ash/ash.gyp:ash',
             '../ash/ash_strings.gyp:ash_strings',
-            '../ui/app_list/app_list.gyp:app_list',
             '../ui/message_center/message_center.gyp:message_center',
           ],
         }],
         ['use_aura==1 and use_ash==0 and OS=="linux"', {
           'dependencies': [
             # gtk2 is the only component that can interact with gtk2 in our new
             # world.
             'browser/ui/libgtk2ui/libgtk2ui.gyp:gtk2ui',
           ],
         }],
@@ skipping 334 matching lines @@
             '../third_party/isimpledom/isimpledom.gyp:isimpledom',
             '../ui/app_list/app_list.gyp:app_list',
             '../ui/views/controls/webview/webview.gyp:webview',
             '../ui/views/views.gyp:views',
           ],
           'export_dependent_settings': [
             '../ui/views/controls/webview/webview.gyp:webview',
             '../ui/views/views.gyp:views',
           ],
           'sources': [
-            'browser/ui/app_list/app_list_view_delegate.cc',
-            'browser/ui/app_list/app_list_view_delegate.h',
-            'browser/ui/app_list/apps_model_builder.cc',
-            'browser/ui/app_list/apps_model_builder.h',
-            'browser/ui/app_list/chrome_app_list_item.h',
-            'browser/ui/app_list/extension_app_item.cc',
-            'browser/ui/app_list/extension_app_item.h',
-            'browser/ui/app_list/search_builder.cc',
-            'browser/ui/app_list/search_builder.h',
             'browser/ui/views/network_profile_bubble_view.cc',
             'browser/ui/views/network_profile_bubble_view.h',
             'browser/ui/webui/conflicts_ui.cc',
             'browser/ui/webui/conflicts_ui.h',
           ],
           'sources!': [
             'browser/ui/certificate_dialogs.cc',
             'browser/ui/certificate_dialogs.h',
             'browser/ui/crypto_module_password_dialog.cc',
             'browser/ui/crypto_module_password_dialog_nss.cc',
@@ skipping 79 matching lines @@
             ['include', '^browser/ui/views/select_file_dialog_extension_factory.cc'],
             ['include', '^browser/ui/views/select_file_dialog_extension_factory.h'],
           ]}, {
           'sources/': [
             ['exclude', '^browser/ui/views/select_file_dialog_extension.cc'],
             ['exclude', '^browser/ui/views/select_file_dialog_extension.h'],
             ['exclude', '^browser/ui/views/select_file_dialog_extension_factory.cc'],
             ['exclude', '^browser/ui/views/select_file_dialog_extension_factory.h'],
           ]}
         ],
+        ['enable_app_list==1', {
+          'dependencies': [
+            '../ui/app_list/app_list.gyp:app_list',
+          ],
+        }, { # else: enable_app_list==0
+          'sources/': [
+            ['exclude', '^browser/ui/views/app_list/'],
+            ['exclude', '^browser/ui/app_list/'],
+          ]
+        }],
       ],
     },
   ],
 }