Disable material design downloads UI from some tests.

chrome/browser/ui/browser_navigator_browsertest.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/browser_navigator_browsertest.h"
 
 #include "base/command_line.h"
 #include "base/prefs/pref_service.h"
 #include "base/strings/string_util.h"
 #include "base/strings/utf_string_conversions.h"
@@ skipping 184 matching lines @@
   EXPECT_EQ(browser, params.browser);
   EXPECT_EQ(1, browser->tab_strip_model()->count());
   EXPECT_EQ(GURL(url::kAboutBlankURL),
             browser->tab_strip_model()->GetActiveWebContents()->GetURL());
 }
 
 void BrowserNavigatorTest::SetUpCommandLine(base::CommandLine* command_line) {
   // Disable settings-in-a-window so that we can use the settings page and
   // sub-pages to test browser navigation.
   command_line->AppendSwitch(::switches::kDisableSettingsWindow);
+
+  // Disable new downloads UI as it is very very slow. https://crbug.com/526577
+  // TODO(dbeam): remove this once the downloads UI is not slow.
+  command_line->AppendSwitch(switches::kDisableMaterialDesignDownloads);
 }
 
 void BrowserNavigatorTest::Observe(
     int type,
     const content::NotificationSource& source,
     const content::NotificationDetails& details) {
   switch (type) {
     case content::NOTIFICATION_WEB_CONTENTS_RENDER_VIEW_HOST_CREATED: {
       ++this->created_tab_contents_count_;
       break;
@@ skipping 1191 matching lines @@
   EXPECT_EQ(expected_title, params.target_contents->GetTitle());
   // GURL always keeps non-ASCII characters escaped, but check them anyways.
   EXPECT_EQ(GURL(expected_url).spec(), params.target_contents->GetURL().spec());
   // Check the omnibox text. It should have escaped RTL with unescaped text.
   LocationBar* location_bar = browser()->window()->GetLocationBar();
   OmniboxView* omnibox_view = location_bar->GetOmniboxView();
   EXPECT_EQ(base::UTF8ToUTF16(expected_url), omnibox_view->GetText());
 }
 
 }  // namespace