Fix missing SB2DatabaseFailure histogram entries

chrome/browser/safe_browsing/safe_browsing_database.h

Index: chrome/browser/safe_browsing/safe_browsing_database.h
diff --git a/chrome/browser/safe_browsing/safe_browsing_database.h b/chrome/browser/safe_browsing/safe_browsing_database.h
index 8575a0baecf18f7fc394c4260bccd147c8d490ac..e7c62772c11ce291ab787695691f45ada5e348e0 100644
--- a/chrome/browser/safe_browsing/safe_browsing_database.h
+++ b/chrome/browser/safe_browsing/safe_browsing_database.h
@@ -237,44 +237,45 @@ class SafeBrowsingDatabase {
   static base::FilePath UnwantedSoftwareDBFilename(
       const base::FilePath& db_filename);
 
-  // Enumerate failures for histogramming purposes.  DO NOT CHANGE THE
-  // ORDERING OF THESE VALUES.
+  // SafeBrowsing Database failure types for histogramming purposes.  Explicitly
+  // label new values and do not re-use old values. Also make sure to reflect
+  // modifications made below in the SB2DatabaseFailure histogram enum.
   enum FailureType {
-    FAILURE_DATABASE_CORRUPT,
-    FAILURE_DATABASE_CORRUPT_HANDLER,
-    FAILURE_BROWSE_DATABASE_UPDATE_BEGIN,
-    FAILURE_BROWSE_DATABASE_UPDATE_FINISH,
-    FAILURE_DATABASE_FILTER_MISSING_OBSOLETE,
-    FAILURE_DATABASE_FILTER_READ_OBSOLETE,
-    FAILURE_DATABASE_FILTER_WRITE_OBSOLETE,
-    FAILURE_DATABASE_FILTER_DELETE,
-    FAILURE_DATABASE_STORE_MISSING,
-    FAILURE_DATABASE_STORE_DELETE,
-    FAILURE_DOWNLOAD_DATABASE_UPDATE_BEGIN,
-    FAILURE_DOWNLOAD_DATABASE_UPDATE_FINISH,
-    FAILURE_WHITELIST_DATABASE_UPDATE_BEGIN,
-    FAILURE_WHITELIST_DATABASE_UPDATE_FINISH,
-    FAILURE_BROWSE_PREFIX_SET_READ,
-    FAILURE_BROWSE_PREFIX_SET_WRITE,
-    FAILURE_BROWSE_PREFIX_SET_DELETE,
-    FAILURE_EXTENSION_BLACKLIST_UPDATE_BEGIN,
-    FAILURE_EXTENSION_BLACKLIST_UPDATE_FINISH,
-    FAILURE_EXTENSION_BLACKLIST_DELETE,
-    FAILURE_SIDE_EFFECT_FREE_WHITELIST_UPDATE_BEGIN,
-    FAILURE_SIDE_EFFECT_FREE_WHITELIST_UPDATE_FINISH,
-    FAILURE_SIDE_EFFECT_FREE_WHITELIST_DELETE,
-    FAILURE_SIDE_EFFECT_FREE_WHITELIST_PREFIX_SET_READ,
-    FAILURE_SIDE_EFFECT_FREE_WHITELIST_PREFIX_SET_WRITE,
-    FAILURE_SIDE_EFFECT_FREE_WHITELIST_PREFIX_SET_DELETE,
-    FAILURE_IP_BLACKLIST_UPDATE_BEGIN,
-    FAILURE_IP_BLACKLIST_UPDATE_FINISH,
-    FAILURE_IP_BLACKLIST_UPDATE_INVALID,
-    FAILURE_IP_BLACKLIST_DELETE,
-    FAILURE_UNWANTED_SOFTWARE_DATABASE_UPDATE_BEGIN,
-    FAILURE_UNWANTED_SOFTWARE_DATABASE_UPDATE_FINISH,
-    FAILURE_UNWANTED_SOFTWARE_PREFIX_SET_READ,
-    FAILURE_UNWANTED_SOFTWARE_PREFIX_SET_WRITE,
-    FAILURE_UNWANTED_SOFTWARE_PREFIX_SET_DELETE,
+    FAILURE_DATABASE_CORRUPT = 0,
+    FAILURE_DATABASE_CORRUPT_HANDLER = 1,
+    FAILURE_BROWSE_DATABASE_UPDATE_BEGIN = 2,
+    FAILURE_BROWSE_DATABASE_UPDATE_FINISH = 3,
+    FAILURE_DATABASE_FILTER_MISSING_OBSOLETE = 4,
+    FAILURE_DATABASE_FILTER_READ_OBSOLETE = 5,
+    FAILURE_DATABASE_FILTER_WRITE_OBSOLETE = 6,
+    FAILURE_DATABASE_FILTER_DELETE = 7,
+    FAILURE_DATABASE_STORE_MISSING = 8,
+    FAILURE_DATABASE_STORE_DELETE = 9,
+    FAILURE_DOWNLOAD_DATABASE_UPDATE_BEGIN = 10,
+    FAILURE_DOWNLOAD_DATABASE_UPDATE_FINISH = 11,
+    FAILURE_WHITELIST_DATABASE_UPDATE_BEGIN = 12,
+    FAILURE_WHITELIST_DATABASE_UPDATE_FINISH = 13,
+    FAILURE_BROWSE_PREFIX_SET_READ = 14,
+    FAILURE_BROWSE_PREFIX_SET_WRITE = 15,
+    FAILURE_BROWSE_PREFIX_SET_DELETE = 16,
+    FAILURE_EXTENSION_BLACKLIST_UPDATE_BEGIN = 17,
+    FAILURE_EXTENSION_BLACKLIST_UPDATE_FINISH = 18,
+    FAILURE_EXTENSION_BLACKLIST_DELETE = 19,
+    FAILURE_SIDE_EFFECT_FREE_WHITELIST_UPDATE_BEGIN = 20,
+    FAILURE_SIDE_EFFECT_FREE_WHITELIST_UPDATE_FINISH = 21,
+    FAILURE_SIDE_EFFECT_FREE_WHITELIST_DELETE = 22,
+    FAILURE_SIDE_EFFECT_FREE_WHITELIST_PREFIX_SET_READ = 23,
+    FAILURE_SIDE_EFFECT_FREE_WHITELIST_PREFIX_SET_WRITE = 24,
+    FAILURE_SIDE_EFFECT_FREE_WHITELIST_PREFIX_SET_DELETE = 25,
+    FAILURE_IP_BLACKLIST_UPDATE_BEGIN = 26,
+    FAILURE_IP_BLACKLIST_UPDATE_FINISH = 27,
+    FAILURE_IP_BLACKLIST_UPDATE_INVALID = 28,
+    FAILURE_IP_BLACKLIST_DELETE = 29,
+    FAILURE_UNWANTED_SOFTWARE_DATABASE_UPDATE_BEGIN = 30,
+    FAILURE_UNWANTED_SOFTWARE_DATABASE_UPDATE_FINISH = 31,
+    FAILURE_UNWANTED_SOFTWARE_PREFIX_SET_READ = 32,
+    FAILURE_UNWANTED_SOFTWARE_PREFIX_SET_WRITE = 33,
+    FAILURE_UNWANTED_SOFTWARE_PREFIX_SET_DELETE = 34,
 
     // Memory space for histograms is determined by the max.  ALWAYS
     // ADD NEW VALUES BEFORE THIS ONE.