Add a dependency on Xrandr since it fails to link DumpRenderTree of WebKit.

ui/ui.gyp

 # 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.
 
 {
   'variables': {
     'chromium_code': 1,
   },
   'includes': [
     'ui_resources.gypi',
@@ skipping 709 matching lines @@
             ],
           },
         }],
         ['use_x11==1', {
           'all_dependent_settings': {
             'ldflags': [
               '-L<(PRODUCT_DIR)',
             ],
             'link_settings': {
               'libraries': [
-                '-lX11 -lXcursor',
+                '-lX11',
+                '-lXcursor',
+                '-lXrandr',  # For XRR* function calls in x11_util.cc.
               ],
             },
           },
         }, {  # use_x11==0
           'sources/': [
             ['exclude', 'base/keycodes/keyboard_code_conversion_x.*'],
             ['exclude', 'base/x/*'],
           ],
         }],
         ['toolkit_views==0', {
@@ skipping 36 matching lines @@
   ],
   'conditions': [
     ['inside_chromium_build == 1 and OS != "ios"', {
       # TODO(ios): The ui tests do not compile yet on iOS.
       'includes': [
         'ui_unittests.gypi',
       ]},
     ],
   ],
 }