Make TestingProfile auto-create incognito profiles.

chrome/browser/ui/bookmarks/bookmark_bubble_sign_in_delegate_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 "chrome/browser/ui/bookmarks/bookmark_bubble_sign_in_delegate.h"
 
 #include "base/basictypes.h"
 #include "base/command_line.h"
 #include "base/memory/scoped_ptr.h"
 #include "chrome/browser/extensions/test_extension_service.h"
@@ skipping 58 matching lines @@
 
   // A new tab should have been opened and the browser should be visible.
   int tab_count = browser()->tab_strip_model()->count();
   EXPECT_EQ(starting_tab_count + 1, tab_count);
   EXPECT_LE(1,
             static_cast<BookmarkBubbleSignInDelegateTest::Window*>(
                 browser()->window())->show_count());
 }
 
 TEST_F(BookmarkBubbleSignInDelegateTest, OnSignInLinkClickedIncognito) {
-  // Create an incognito browser.
-  TestingProfile::Builder incognito_profile_builder;
-  incognito_profile_builder.SetIncognito();
-  scoped_ptr<TestingProfile> incognito_profile =
-      incognito_profile_builder.Build();
-  incognito_profile->SetOriginalProfile(profile());
-  profile()->SetOffTheRecordProfile(incognito_profile.PassAs<Profile>());
-
   scoped_ptr<BrowserWindow> incognito_window;
   incognito_window.reset(CreateBrowserWindow());
   Browser::CreateParams params(browser()->profile()->GetOffTheRecordProfile(),
                                browser()->host_desktop_type());
   params.window = incognito_window.get();
   scoped_ptr<Browser> incognito_browser;
   incognito_browser.reset(new Browser(params));
 
   int starting_tab_count_normal = browser()->tab_strip_model()->count();
   int starting_tab_count_incognito =
@@ skipping 49 matching lines @@
   // visible.
   int tab_count = extra_browser->tab_strip_model()->count();
   EXPECT_EQ(starting_tab_count + 1, tab_count);
   EXPECT_LE(1,
             static_cast<BookmarkBubbleSignInDelegateTest::Window*>(
                 extra_window.get())->show_count());
 
   // Required to avoid a crash when the browser is deleted.
   extra_browser->tab_strip_model()->CloseAllTabs();
 }