[MD] Remove new incognito styling from guest mode.

chrome/browser/ui/aura/chrome_browser_main_extra_parts_aura.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 "chrome/browser/ui/aura/chrome_browser_main_extra_parts_aura.h"
 
 #include "base/command_line.h"
 #include "base/run_loop.h"
 #include "build/build_config.h"
 #include "chrome/browser/chrome_browser_main.h"
@@ skipping 50 matching lines @@
         window->GetNativeWindowProperty(Profile::kProfileKey));
   }
 
   if (profile && !profile->GetPrefs()->GetBoolean(prefs::kUsesSystemTheme)) {
     // Only toplevel browser windows and CONTROL type windows (such as the find
     // in page bar) should use special theming for off the record mode.
     // WINDOW_TYPE_NORMAL is not enough to distinguish browser windows because
     // it also encompasses dialogs.
     bool eligible_for_otr = window->type() == ui::wm::WINDOW_TYPE_CONTROL ||
                             BrowserView::GetBrowserViewForNativeWindow(window);
-    if (eligible_for_otr && profile->IsOffTheRecord())
+    if (eligible_for_otr &&
+        profile->GetProfileType() == Profile::INCOGNITO_PROFILE) {
       return ui::NativeThemeDarkAura::instance();
+    }
 
     return ui::NativeThemeAura::instance();
   }
 
   return nullptr;
 }
 #endif
 
 #if !defined(OS_CHROMEOS) && defined(USE_ASH)
 // Returns the desktop this process was initially launched in.
@@ skipping 108 matching lines @@
                            chrome::MESSAGE_BOX_TYPE_WARNING);
 
     // Avoids gpu_process_transport_factory.cc(153)] Check failed:
     // per_compositor_data_.empty() when quit is chosen.
     base::RunLoop().RunUntilIdle();
 
     exit(EXIT_FAILURE);
   }
 }
 #endif