Update legacy Tuple-using code.

chrome/browser/search/instant_service_unittest.cc

 // Copyright 2013 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 <string>
 #include <vector>
 
 #include "base/memory/scoped_ptr.h"
 #include "base/metrics/field_trial.h"
 #include "base/strings/string_util.h"
@@ skipping 90 matching lines @@
   rph->sink().ClearMessages();
   instant_service_->Observe(
       content::NOTIFICATION_RENDERER_PROCESS_CREATED,
       content::Source<content::MockRenderProcessHost>(rph.get()),
       content::NotificationService::NoDetails());
   EXPECT_EQ(1U, rph->sink().message_count());
   const IPC::Message* msg = rph->sink().GetMessageAt(0);
   ASSERT_TRUE(msg);
   ChromeViewMsg_SetSearchURLs::Param params;
   ChromeViewMsg_SetSearchURLs::Read(msg, &params);
-  std::vector<GURL> search_urls = params.a;
-  GURL new_tab_page_url = params.b;
+  std::vector<GURL> search_urls = get<0>(params);
+  GURL new_tab_page_url = get<1>(params);
   EXPECT_EQ(2U, search_urls.size());
   EXPECT_EQ("https://www.google.com/alt#quux=", search_urls[0].spec());
   EXPECT_EQ("https://www.google.com/url?bar=", search_urls[1].spec());
   EXPECT_EQ("https://www.google.com/newtab", new_tab_page_url.spec());
 }
 
 TEST_F(InstantServiceTest, InstantSearchEnabled) {
   EXPECT_NE(static_cast<InstantSearchPrerenderer*>(NULL),
             GetInstantSearchPrerenderer());
 }
@@ skipping 33 matching lines @@
   NotifyGoogleBaseURLUpdate(new_base_url);
   EXPECT_NE(old_prerenderer, GetInstantSearchPrerenderer());
 }
 
 TEST_F(InstantServiceTest, OmniboxStartMarginChanged) {
   int new_start_margin = 92;
   EXPECT_CALL(*instant_service_observer_.get(),
               OmniboxStartMarginChanged(new_start_margin)).Times(1);
   UpdateOmniboxStartMargin(new_start_margin);
 }