Remove instant confirmation dialog that is displayed the first time the instant checkbox is clicked.

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 301 matching lines @@
 
 // Help URL for the settings page's search feature.
 extern const char kSettingsSearchHelpURL[];
 
 // "About" URL for the translate bar's options menu.
 extern const char kAboutGoogleTranslateURL[];
 
 // Help URL for the Omnibox setting.
 extern const char kOmniboxLearnMoreURL[];
 
-// "Learn more" URL for the Instant feature.
-extern const char kInstantLearnMoreURL[];
-
 // "What do these mean?" URL for the Page Info bubble.
 extern const char kPageInfoHelpCenterURL[];
 
 // "Learn more" URL for "Aw snap" page.
 extern const char kCrashReasonURL[];
 
 // "Learn more" URL for killed tab page.
 extern const char kKillReasonURL[];
 
 // "Learn more" URL for the Privacy section under Options.
@@ skipping 109 matching lines @@
 // 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_