Move app launch metric recording code from NTP to chrome/common.

chrome/common/extensions/extension_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.
 
 #ifndef CHROME_COMMON_EXTENSIONS_EXTENSION_CONSTANTS_H_
 #define CHROME_COMMON_EXTENSIONS_EXTENSION_CONSTANTS_H_
 
 #include <string>
 
 #include "base/basictypes.h"
@@ skipping 91 matching lines @@
 
 // The extension id used for testing streamsPrivate
 extern const char kStreamsPrivateTestExtensionId[];
 
 // The extension id of the Youtube application.
 extern const char kYoutubeAppId[];
 
 // The extension id of the in-app payments support application.
 extern const char kInAppPaymentsSupportAppId[];
 
-// The name of the app launch histogram.
-extern const char kAppLaunchHistogram[];
-
-// The name of the app launch histogram for platform apps.
-extern const char kPlatformAppLaunchHistogram[];
-
 // The buckets used for app launches.
 enum AppLaunchBucket {
   // Launch from NTP apps section while maximized.
   APP_LAUNCH_NTP_APPS_MAXIMIZED,
 
   // Launch from NTP apps section while collapsed.
   APP_LAUNCH_NTP_APPS_COLLAPSED,
 
   // Launch from NTP apps section while in menu mode.
   APP_LAUNCH_NTP_APPS_MENU,
@@ skipping 132 matching lines @@
 // The path part of the file system url used for media file systems.
 extern const char kMediaFileSystemPathPart[];
 
 // The key used for signing some pieces of data from the webstore.
 extern const uint8 kWebstoreSignaturesPublicKey[];
 extern const int kWebstoreSignaturesPublicKeySize;
 
 }  // namespace extension_misc
 
 #endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_CONSTANTS_H_