Remove omnibox_search_hint.(cc,h).

chrome/common/pref_names.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.
 
 // Constants for the names of various preferences, for easier changing.
 
 #ifndef CHROME_COMMON_PREF_NAMES_H_
 #define CHROME_COMMON_PREF_NAMES_H_
 
 #include <stddef.h>
@@ skipping 356 matching lines @@
 #endif
 extern const char kCheckDefaultBrowser[];
 #if defined(OS_WIN)
 extern const char kSuppressSwitchToMetroModeOnSetDefault[];
 #endif
 extern const char kDefaultBrowserSettingEnabled[];
 #if defined(OS_MACOSX)
 extern const char kShowUpdatePromotionInfoBar[];
 #endif
 extern const char kUseCustomChromeFrame[];
-extern const char kShowOmniboxSearchHint[];
 extern const char kDesktopNotificationPosition[];
 extern const char kDefaultContentSettings[];
 extern const char kContentSettingsClearOnExitMigrated[];
 extern const char kContentSettingsVersion[];
 extern const char kContentSettingsPatternPairs[];
 extern const char kContentSettingsDefaultWhitelistVersion[];
 extern const char kContentSettingsPluginWhitelist[];
 extern const char kBlockThirdPartyCookies[];
 extern const char kClearSiteDataOnExit[];
 extern const char kDefaultZoomLevel[];
@@ skipping 532 matching lines @@
 extern const char kAppListLaunchCount[];
 extern const char kLastAppListAppLaunchPing[];
 extern const char kAppListAppLaunchCount[];
 
 extern const char kDRMSalt[];
 extern const char kEnableDRM[];
 
 }  // namespace prefs
 
 #endif  // CHROME_COMMON_PREF_NAMES_H_