Implement local NTP for fallback.

chrome/common/url_constants.h

 // 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.
 
 // Contains constants for known URLs and portions thereof.
 
 #ifndef CHROME_COMMON_URL_CONSTANTS_H_
 #define CHROME_COMMON_URL_CONSTANTS_H_
 
 #include "build/build_config.h"
@@ skipping 410 matching lines @@
 //  2. Browser: Assuming they got by #1, the scheme checks in
 //     URLDataSource::ShouldServiceRequest will deny the request,
 //  3. Browser: for specific sub-classes of URLDataSource, like ThemeSource
 //     there are additional Instant-PID checks that make sure the request is
 //     coming from a blessed Instant process, and deny the request.
 extern const char kChromeSearchScheme[];
 
 // The local omnibox host and pages under chrome-search.
 extern const char kChromeSearchLocalOmniboxPopupHost[];
 extern const char kChromeSearchLocalOmniboxPopupURL[];
+extern const char kChromeSearchLocalNtpHost[];
+extern const char kChromeSearchLocalNtpUrl[];
 
 // Host for search suggestions iframes.
 extern const char kChromeSearchSuggestionHost[];
 
 #if defined(OS_CHROMEOS)
 extern const char kCrosScheme[];
 extern const char kDriveScheme[];
 
 // "Learn more" URL for the Cloud Print section under Options.
 extern const char kCloudPrintLearnMoreURL[];
 #endif
 
 // Parameters that get appended to force SafeSearch.
 extern const char kSafeSearchSafeParameter[];
 extern const char kSafeSearchSsuiParameter[];
 
 // The URL for the "Learn more" link in the media access infobar.
 extern const char kMediaAccessLearnMoreUrl[];
 
 }  // namespace chrome
 
 #endif  // CHROME_COMMON_URL_CONSTANTS_H_