Migrate old Shortcuts DB data to conform to new type values

chrome/browser/history/shortcuts_database.cc

Index: chrome/browser/history/shortcuts_database.cc
diff --git a/chrome/browser/history/shortcuts_database.cc b/chrome/browser/history/shortcuts_database.cc
index 51d6f09293fbffe58da621bfab05911739d5a9d8..1f7d8ef6973e8fc4b56e178630e23ba7dfb14934 100644
--- a/chrome/browser/history/shortcuts_database.cc
+++ b/chrome/browser/history/shortcuts_database.cc
@@ -11,11 +11,18 @@
 #include "base/logging.h"
 #include "base/strings/stringprintf.h"
 #include "base/time/time.h"
+#include "sql/meta_table.h"
 #include "sql/statement.h"
 #include "sql/transaction.h"
 
 namespace {
 
+// Current version number. We write databases at the "current" version number,
+// but any previous version that can read the "compatible" one can make do with
+// or database without *too* many bad effects.

[Peter Kasting, 2014/02/12 00:27:50]

Nit: or -> our

[Anuj, 2014/02/12 23:54:40]

Done.

+const int kCurrentVersionNumber = 1;
+const int kCompatibleVersionNumber = 1;
+
 void BindShortcutToStatement(
     const history::ShortcutsBackend::Shortcut& shortcut,
     sql::Statement* s) {
@@ -196,6 +203,25 @@ bool ShortcutsDatabase::EnsureTable() {
         transaction.Commit();
   }
 
+  if (!sql::MetaTable::DoesTableExist(&db_)) {
+    meta_table_.Init(&db_, kCurrentVersionNumber, kCompatibleVersionNumber);
+    sql::Transaction transaction(&db_);
+    transaction.Begin();

[Peter Kasting, 2014/02/12 00:27:50]

Nit: Include this call in the return statement

You may want to also structure this like a "if (!...) return false;" that falls
through to the subsequent code (which is today just a "return true") in order to
be less likely to break if we add more migration steps in the future.

[Anuj, 2014/02/12 23:54:40]

Done.

+    return
+      // Migrate old SEARCH_OTHER_ENGINE values to the new type value.
+      db_.Execute(base::StringPrintf("UPDATE omni_box_shortcuts "
+          "SET type = 13 WHERE type = 9").c_str()) &&
+      // Migrate old EXTENSION_APP values to the new type value.
+      db_.Execute(base::StringPrintf("UPDATE omni_box_shortcuts "
+           "SET type = 14 WHERE type = 10").c_str()) &&
+      // Migrate old CONTACT values to the new type value.
+      db_.Execute(base::StringPrintf("UPDATE omni_box_shortcuts "
+           "SET type = 15 WHERE type = 11").c_str()) &&
+      // Migrate old BOOKMARK_TITLE values to the new type value.
+      db_.Execute(base::StringPrintf("UPDATE omni_box_shortcuts "
+           "SET type = 16 WHERE type = 12").c_str()) &&
+      transaction.Commit();
+  }
   return true;
 }