IndexedDB: More database<->transaction relationship simplification

content/browser/indexed_db/indexed_db_transaction_coordinator.cc

 // Copyright (c) 2013 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 "content/browser/indexed_db/indexed_db_transaction_coordinator.h"
 
 #include "base/basictypes.h"
 #include "base/logging.h"
 #include "content/browser/indexed_db/indexed_db_transaction.h"
 
@@ skipping 10 matching lines @@
     scoped_refptr<IndexedDBTransaction> transaction) {
   DCHECK(!queued_transactions_.count(transaction));
   DCHECK(!started_transactions_.count(transaction));
   DCHECK_EQ(IndexedDBTransaction::CREATED, transaction->state());
 
   queued_transactions_.insert(transaction);
   ProcessQueuedTransactions();
 }
 
 void IndexedDBTransactionCoordinator::DidFinishTransaction(
-    scoped_refptr<IndexedDBTransaction> transaction) {
+    IndexedDBTransaction* transaction) {
   if (queued_transactions_.count(transaction)) {
     DCHECK(!started_transactions_.count(transaction));
     queued_transactions_.erase(transaction);
   } else {
     DCHECK(started_transactions_.count(transaction));
     started_transactions_.erase(transaction);
   }
 
   ProcessQueuedTransactions();
 }
 
+bool IndexedDBTransactionCoordinator::IsRunningVersionChangeTransaction()
+    const {
+  return !started_transactions_.empty() &&
+         (*started_transactions_.begin())->mode() ==
+             indexed_db::TRANSACTION_VERSION_CHANGE;
+}
+
 #ifndef NDEBUG
 // Verifies internal consistency while returning whether anything is found.
 bool IndexedDBTransactionCoordinator::IsActive(
     IndexedDBTransaction* transaction) {
   bool found = false;
   if (queued_transactions_.count(transaction))
     found = true;
   if (started_transactions_.count(transaction)) {
     DCHECK(!found);
     found = true;
@@ skipping 17 matching lines @@
     result.push_back(*it);
   }
 
   return result;
 }
 
 void IndexedDBTransactionCoordinator::ProcessQueuedTransactions() {
   if (queued_transactions_.empty())
     return;
 
-  DCHECK(started_transactions_.empty() ||
-         (*started_transactions_.begin())->mode() !=
-             indexed_db::TRANSACTION_VERSION_CHANGE);
+  DCHECK(!IsRunningVersionChangeTransaction());
 
   // The locked_scope set accumulates the ids of object stores in the scope of
   // running read/write transactions. Other read-write transactions with
   // stores in this set may not be started. Read-only transactions may start,
   // taking a snapshot of the database, which does not include uncommitted
   // data. ("Version change" transactions are exclusive, but handled by the
   // connection sequencing in IndexedDBDatabase.)
   std::set<int64> locked_scope;
   for (TransactionSet::const_iterator it = started_transactions_.begin();
        it != started_transactions_.end();
@@ skipping 59 matching lines @@
       return true;
 
     case indexed_db::TRANSACTION_READ_WRITE:
       return !DoSetsIntersect(transaction->scope(), locked_scope);
   }
   NOTREACHED();
   return false;
 }
 
 }  // namespace content