Use the WebTestProxy for layout tests in content_shell

content/content_layouttest_support.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': 'content_layouttest_support',
+      'conditions': [
+        ['component=="shared_library" or OS=="ios"', {
+          'type': 'none',
+        }, {
+          'type': 'static_library',
+          'variables': {
+            'chromium_code': 1,
+          },
+          'dependencies': [
+            'content_renderer',
+            '<(webkit_src_dir)/Tools/DumpRenderTree/DumpRenderTree.gyp/DumpRenderTree.gyp:TestRunner',
+          ],
+          'include_dirs': [
+            '..',
+          ],
+          'sources': [
+            'layouttest_support/content_layouttest_support.cc',
+          ],
+        }],
+      ],
+    },
+  ]
+}