Hide X11 dependencies when use_x11=0.

chrome/chrome_browser.gypi

 # Copyright 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',
       'type': 'static_library',
       'variables': { 'enable_wexit_time_destructors': 1, },
@@ skipping 3434 matching lines @@
               ],
             }],
           ],
         }],
         ['OS=="linux"', {
           'conditions': [
             ['use_aura==1', {
               'dependencies': [
                 '../build/linux/system.gyp:dbus',
                 '../build/linux/system.gyp:fontconfig',
-                '../build/linux/system.gyp:x11',
                 '../dbus/dbus.gyp:dbus',
               ],
               'sources/': [
                 ['exclude', '^browser/platform_util_common_linux.cc'],
               ],
             }],
             # GTK build only
             ['toolkit_uses_gtk==1', {
               'sources/': [
                 ['exclude', '^browser/lifetime/application_lifetime_stub.cc'],
               ],
             }],
+            # x11 build
+            ['use_x11==1', {
+              'dependencies': [
+                '../build/linux/system.gyp:x11',
+              ],
+            }],
           ],
         }],
         ['enable_plugin_installation==0', {
           'sources!': [
             'browser/plugins/plugin_installer.cc',
             'browser/plugins/plugin_installer.h',
             'browser/plugins/plugin_installer_observer.cc',
             'browser/plugins/plugin_installer_observer.h',
             'browser/plugins/plugins_resource_service.cc',
             'browser/plugins/plugins_resource_service.h',
@@ skipping 264 matching lines @@
             'package_name': 'org/chromium/chrome/browser/ui/toolbar',
             'template_deps': ['browser/ui/toolbar/toolbar_model_security_level_list.h'],
           },
           'includes': [ '../build/android/java_cpp_template.gypi' ],
         },
       ],
      },
     ],
   ],
 }