Add a histogram for tracking web store promo

chrome/common/extensions/extension_constants.h

 // Copyright (c) 2010 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_
 #pragma once
 
 #include "base/basictypes.h"
 
@@ skipping 206 matching lines @@
 
 namespace extension_misc {
   const int kUnknownWindowId = -1;
 
   // The extension id of the bookmark manager.
   extern const char* kBookmarkManagerId;
 
   // The extension id of the Web Store component application.
   extern const char* kWebStoreAppId;
 
+  // Web Store app id used in the new tab page.

[Erik does not do reviews, 2010/11/10 23:29:51]

I don't get it.  How can we have two different app ids for the same app?  This
seems like it would break some important stuff.

+  extern const char* kNTPWebStoreAppId;
+
   // Note: this structure is an ASN.1 which encodes the algorithm used
   // with its parameters. This is defined in PKCS #1 v2.1 (RFC 3447).
   // It is encoding: { OID sha1WithRSAEncryption      PARAMETERS NULL }
   const uint8 kSignatureAlgorithm[15] = {
     0x30, 0x0d, 0x06, 0x09, 0x2a, 0x86, 0x48, 0x86,
     0xf7, 0x0d, 0x01, 0x01, 0x05, 0x05, 0x00
   };
 
   // Don't remove items or change the order of this enum.  It's used in
   // histograms and preferences.
   enum LaunchContainer {
     LAUNCH_WINDOW,
     LAUNCH_PANEL,
     LAUNCH_TAB
   };
+
+  // These are the buckets used in the apps promo histogram.
+  enum AppsPromoBuckets {
+    LAUNCH_APP,
+    LAUNCH_WEB_STORE,
+    CLOSE_PROMO,
+    EXPIRE_PROMO,
+    MAX = EXPIRE_PROMO

[Erik does not do reviews, 2010/11/10 23:29:51]

this is wrong.  From histogram.h: "the samples should always be less than
boundary_value".

+  };
 }  // extension_misc
 
 #endif  // CHROME_COMMON_EXTENSIONS_EXTENSION_CONSTANTS_H_