Don't display navigation error pages during layout tests

content/test/layouttest_support.cc

 // 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.
 
 #include "content/public/test/layouttest_support.h"
 
 #include "base/callback.h"
 #include "base/lazy_instance.h"
 #include "content/common/gpu/image_transport_surface.h"
 #include "content/renderer/devtools/devtools_client.h"
@@ skipping 73 matching lines @@
 
 void EnableShortCircuitSizeUpdates() {
   RenderThreadImpl::current()->set_short_circuit_size_updates(true);
 }
 
 void ForceResizeRenderView(RenderView* render_view,
                            const WebKit::WebSize& new_size) {
   static_cast<RenderViewImpl*>(render_view)->didAutoResize(new_size);
 }
 
+void DisableNavigationErrorPages() {
+  RenderThreadImpl::current()->set_skip_error_pages(true);
+}
+
 }  // namespace content