Ensure that TemplateURLs created from old database entries without sync_guids generate their own ...

chrome/browser/webdata/keyword_table.cc

 // Copyright (c) 2011 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.
 
 #include "chrome/browser/webdata/keyword_table.h"
 
 #include "base/logging.h"
 #include "base/string_split.h"
 #include "base/string_util.h"
 #include "base/utf_string_conversions.h"
@@ skipping 171 matching lines @@
     template_url->set_autogenerate_keyword(s.ColumnInt(13) == 1);
 
     template_url->set_logo_id(s.ColumnInt(14));
 
     template_url->set_created_by_policy(s.ColumnBool(15));
 
     template_url->SetInstantURL(s.ColumnString(16), 0, 0);
 
     template_url->set_last_modified(Time::FromTimeT(s.ColumnInt64(17)));
 
-    template_url->set_sync_guid(s.ColumnString(18));
+    // If the persisted sync_guid was empty, we ignore it and allow the TURL to
+    // keep its generated GUID.
+    if (!s.ColumnString(18).empty())
+      template_url->set_sync_guid(s.ColumnString(18));
 
     urls->push_back(template_url);
   }
   return s.Succeeded();
 }
 
 bool KeywordTable::UpdateKeyword(const TemplateURL& url) {
   DCHECK(url.id());
   // Be sure to change kUrlIdPosition if you add columns
   sql::Statement s(db_->GetUniqueStatement(
@@ skipping 100 matching lines @@
 
 bool KeywordTable::MigrateToVersion38AddLastModifiedColumn() {
   return db_->Execute(
       "ALTER TABLE keywords ADD COLUMN last_modified INTEGER DEFAULT 0");
 }
 
 bool KeywordTable::MigrateToVersion39AddSyncGUIDColumn() {
   return db_->Execute(
       "ALTER TABLE keywords ADD COLUMN sync_guid VARCHAR");
 }