Mock the LinkDoctor for tests. Should greatly decrease ErrorPage test flakiness.

chrome/browser/google_util.cc

 // Copyright (c) 2006-2008 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 "chrome/browser/google_util.h"
 
 #include <string>
 
 #include "base/string_util.h"
 #include "chrome/browser/browser_process.h"
@@ skipping 13 matching lines @@
   query += param_name + "=" + param_value;
   GURL::Replacements repl;
   repl.SetQueryStr(query);
   return url.ReplaceComponents(repl);
 }
 
 }  // anonymous namespace
 
 namespace google_util {
 
+const char kLinkDoctorBaseURL[] =
+    "http://linkhelp.clients.google.com/tbproxy/lh/fixurl";
+
 GURL AppendGoogleLocaleParam(const GURL& url) {
   return AppendParam(url, "hl",
                      g_browser_process->GetApplicationLocale());
 }
 
 GURL AppendGoogleTLDParam(const GURL& url) {
   const std::string google_domain(
       net::RegistryControlledDomainService::GetDomainAndRegistry(
           GoogleURLTracker::GoogleURL()));
   const size_t first_dot = google_domain.find('.');
   if (first_dot == std::string::npos) {
     NOTREACHED();
     return url;
   }
   return AppendParam(url, "sd", google_domain.substr(first_dot + 1));
 }
 
 }  // namespace google_util