AppCache: Run a quick integrity check on the sqlite database when opening.

webkit/browser/appcache/appcache_database.cc

Index: webkit/browser/appcache/appcache_database.cc
diff --git a/webkit/browser/appcache/appcache_database.cc b/webkit/browser/appcache/appcache_database.cc
index a3dadd9eaf5515cc1f90381f636c5de6e645bfba..48b03e3f33bbe8a5863909f75905720eafd6ab3b 100644
--- a/webkit/browser/appcache/appcache_database.cc
+++ b/webkit/browser/appcache/appcache_database.cc
@@ -1019,7 +1019,7 @@ bool AppCacheDatabase::LazyOpen(bool create_if_needed) {
       db_->Preload();
   }
 
-  if (!opened || !EnsureDatabaseVersion()) {
+  if (!opened || !QuickIntegrityCheck() || !EnsureDatabaseVersion()) {
     LOG(ERROR) << "Failed to open the appcache database.";
     AppCacheHistograms::CountInitResult(
         AppCacheHistograms::SQL_DATABASE_ERROR);
@@ -1039,6 +1039,14 @@ bool AppCacheDatabase::LazyOpen(bool create_if_needed) {
   return true;
 }
 
+bool AppCacheDatabase::QuickIntegrityCheck() {
+  DCHECK(db_.get());
+  std::vector<std::string> messages;
+  if (!db_->QuickIntegrityCheck(&messages))
+    return false;
+  return messages.size() == 1 && messages[0] == "ok";
+}
+
 bool AppCacheDatabase::EnsureDatabaseVersion() {
   if (!sql::MetaTable::DoesTableExist(db_.get()))
     return CreateSchema();