[sql] Convert thumbnails and top-sites databases to auto-recovery.

tools/metrics/histograms/histograms.xml

Index: tools/metrics/histograms/histograms.xml
diff --git a/tools/metrics/histograms/histograms.xml b/tools/metrics/histograms/histograms.xml
index 262ca22a17dafdaaf988794fe64d9b93b08ab987..2feb257d32240cf940b87b54347baeb7673eadc8 100644
--- a/tools/metrics/histograms/histograms.xml
+++ b/tools/metrics/histograms/histograms.xml
@@ -21806,6 +21806,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="History.FaviconsRecoveredPercentage" units="%">
+  <obsolete>
+    No longer tracked as of March 2017.
+  </obsolete>
   <owner>rpop@google.com</owner>
   <summary>
     Size of the recovered Favicons database relative to the original corrupt
@@ -21817,6 +21820,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="History.FaviconsRecoveredRowsFaviconBitmaps">
+  <obsolete>
+    No longer tracked as of March 2017.
+  </obsolete>
   <owner>rpop@google.com</owner>
   <summary>
     Rows recovered from [favicon_bitmaps] table in Favicons recovery.
@@ -21824,11 +21830,17 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="History.FaviconsRecoveredRowsFavicons">
+  <obsolete>
+    No longer tracked as of March 2017.
+  </obsolete>
   <owner>rpop@google.com</owner>
   <summary>Rows recovered from [favicons] table in Favicons recovery.</summary>
 </histogram>
 
 <histogram name="History.FaviconsRecoveredRowsIconMapping">
+  <obsolete>
+    No longer tracked as of March 2017.
+  </obsolete>
   <owner>rpop@google.com</owner>
   <summary>
     Rows recovered from [icon_mapping] table in Favicons recovery.
@@ -21836,6 +21848,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 </histogram>
 
 <histogram name="History.FaviconsRecovery" enum="HistoryFaviconsRecoveryEnum">
+  <obsolete>
+    No longer tracked as of March 2017.
+  </obsolete>
   <owner>rpop@google.com</owner>
   <summary>
     Track results of SQLite database recovery code in thumbnail_database.cc.
@@ -95532,6 +95547,9 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
 
 <enum name="HistoryFaviconsRecoveryEnum" type="int">
   <summary>Error states noted in thumbnail_database.cc recovery code.</summary>
+  <obsolete>
+    History.FaviconsRecovery no longer tracked as of March 2017.
+  </obsolete>
   <int value="0" label="RECOVERY_EVENT_RECOVERED">Successful recovery.</int>
   <int value="1" label="RECOVERY_EVENT_FAILED_SCOPER">
     sql::Recovery failed init.
@@ -95630,7 +95648,7 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="1" label="RECOVERY_EVENT_DEPRECATED">
     Recovery found deprecated version and razed.
   </int>
-  <int value="2" label="RECOVERY_EVENT_FAILED_SCOPER">
+  <int value="2" label="RECOVERY_EVENT_FAILED_SCOPER (obsolete Mar 2017)">
     sql::Recovery failed init.
   </int>
   <int value="3" label="RECOVERY_EVENT_FAILED_META_VERSION">
@@ -95639,13 +95657,14 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="4" label="RECOVERY_EVENT_FAILED_META_WRONG_VERSION">
     Recovery meta table has an unexpected version.
   </int>
-  <int value="5" label="RECOVERY_EVENT_FAILED_META_INIT">
+  <int value="5" label="RECOVERY_EVENT_FAILED_META_INIT (obsolete Mar 2017)">
     Failed sql::MetaTable::Init().
   </int>
-  <int value="6" label="RECOVERY_EVENT_FAILED_SCHEMA_INIT">
+  <int value="6" label="RECOVERY_EVENT_FAILED_SCHEMA_INIT (obsolete Mar 2017)">
     Failed to init target schema.
   </int>
-  <int value="7" label="RECOVERY_EVENT_FAILED_AUTORECOVER_THUMBNAILS">
+  <int value="7"
+      label="RECOVERY_EVENT_FAILED_AUTORECOVER_THUMBNAILS (obsolete Mar 2017)">
     Failed recovery on thumbnails table.
   </int>
   <int value="8" label="RECOVERY_EVENT_FAILED_COMMIT">
@@ -109772,6 +109791,10 @@ from previous Chrome versions.
     Autorecover failed setup with NOTADB, then successfully deleted the
     unrecoverable db and verified that it now works.
   </int>
+  <int value="32" label="RECOVERY_FAILED_AUTORECOVERDB_META_VERSION">
+    Autorecover failed because required version information was missing from the
+    [meta] table.
+  </int>
 </enum>
 
 <enum name="SqliteStatsEnum" type="int">