Reland "Use the same browser instance in the sync confirmation dialog.

chrome/browser/ui/webui/signin/sync_confirmation_handler_unittest.cc

 // Copyright 2016 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/ui/webui/signin/sync_confirmation_handler.h"
 
 #include "base/test/user_action_tester.h"
 #include "base/values.h"
 #include "chrome/browser/profiles/profile_avatar_icon_util.h"
 #include "chrome/browser/signin/account_fetcher_service_factory.h"
@@ skipping 16 matching lines @@
 #include "content/public/test/test_web_ui.h"
 
 const int kExpectedProfileImageSize = 128;
 
 // The dialog needs to be initialized with a height but the actual value doesn't
 // really matter in unit tests.
 const double kDefaultDialogHeight = 350.0;
 
 class TestingSyncConfirmationHandler : public SyncConfirmationHandler {
  public:
-  explicit TestingSyncConfirmationHandler(content::WebUI* web_ui) {
+  explicit TestingSyncConfirmationHandler(Browser* browser,
+                                          content::WebUI* web_ui)
+      : SyncConfirmationHandler(browser) {
     set_web_ui(web_ui);
   }
 
   using SyncConfirmationHandler::HandleConfirm;
   using SyncConfirmationHandler::HandleUndo;
   using SyncConfirmationHandler::HandleInitializedWithSize;
   using SyncConfirmationHandler::HandleGoToSettings;
   using SyncConfirmationHandler::SetUserImageURL;
 };
 
 class SyncConfirmationHandlerTest : public BrowserWithTestWindowTest {
  public:
   SyncConfirmationHandlerTest() : did_user_explicitly_interact(false),
                                   web_ui_(new content::TestWebUI) {}
   void SetUp() override {
     BrowserWithTestWindowTest::SetUp();
     chrome::NewTab(browser());
     web_ui()->set_web_contents(
         browser()->tab_strip_model()->GetActiveWebContents());
 
-    auto handler = base::MakeUnique<TestingSyncConfirmationHandler>(web_ui());
+    auto handler =
+        base::MakeUnique<TestingSyncConfirmationHandler>(browser(), web_ui());
     handler_ = handler.get();
-    sync_confirmation_ui_.reset(
-        new SyncConfirmationUI(web_ui(), std::move(handler)));
+    sync_confirmation_ui_.reset(new SyncConfirmationUI(web_ui()));
+    web_ui()->AddMessageHandler(std::move(handler));
 
     // This dialog assumes the signin flow was completed, which kicks off the
     // SigninManager.
     new OneClickSigninSyncStarter(
         profile(), browser(), "gaia", "foo@example.com", "password",
         "refresh_token", OneClickSigninSyncStarter::CURRENT_PROFILE,
         OneClickSigninSyncStarter::SYNC_WITH_DEFAULT_SETTINGS, nullptr,
         OneClickSigninSyncStarter::NO_CONFIRMATION, GURL(), GURL(),
         OneClickSigninSyncStarter::Callback());
   }
@@ skipping 207 matching lines @@
   EXPECT_FALSE(sync()->IsFirstSetupInProgress());
   EXPECT_TRUE(sync()->IsFirstSetupComplete());
   EXPECT_TRUE(
       SigninManagerFactory::GetForProfile(profile())->IsAuthenticated());
   EXPECT_EQ(0, user_action_tester()->GetActionCount("Signin_Undo_Signin"));
   EXPECT_EQ(1, user_action_tester()->GetActionCount(
       "Signin_Signin_WithDefaultSyncSettings"));
   EXPECT_EQ(0, user_action_tester()->GetActionCount(
       "Signin_Signin_WithAdvancedSyncSettings"));
 }