DatabaseBackend should not post a task to an already terminated database thread

Source/modules/webdatabase/DatabaseBackend.cpp

Index: Source/modules/webdatabase/DatabaseBackend.cpp
diff --git a/Source/modules/webdatabase/DatabaseBackend.cpp b/Source/modules/webdatabase/DatabaseBackend.cpp
index e90628b9a6cf9072cf94b336d2857175e0b1ea31..cd421792e6dd97398d5325b7de7db6ad87edee5a 100644
--- a/Source/modules/webdatabase/DatabaseBackend.cpp
+++ b/Source/modules/webdatabase/DatabaseBackend.cpp
@@ -260,7 +260,7 @@ void DatabaseBackend::trace(Visitor* visitor)
 bool DatabaseBackend::openAndVerifyVersion(bool setVersionInNewDatabase, DatabaseError& error, String& errorMessage)
 {
     TaskSynchronizer synchronizer;
-    if (!databaseContext()->databaseThread() || databaseContext()->databaseThread()->terminationRequested(&synchronizer))
+    if (!databaseContext()->databaseThread() || databaseContext()->databaseThread()->terminationRequested())

[tkent, 2014/09/24 02:14:04]

We should have DatabaseContext::databaseThreadIsAvailable() or something.

[haraken, 2014/09/24 02:23:18]

Done.

         return false;
 
     DatabaseTracker::tracker().prepareToOpenDatabase(this);
@@ -331,7 +331,7 @@ void DatabaseBackend::scheduleTransaction()
     if (m_isTransactionQueueEnabled && !m_transactionQueue.isEmpty())
         transaction = m_transactionQueue.takeFirst();
 
-    if (transaction && databaseContext()->databaseThread()) {
+    if (transaction && databaseContext()->databaseThread() && !databaseContext()->databaseThread()->terminationRequested()) {
         OwnPtr<DatabaseTransactionTask> task = DatabaseTransactionTask::create(transaction);
         WTF_LOG(StorageAPI, "Scheduling DatabaseTransactionTask %p for transaction %p\n", task.get(), task->transaction());
         m_transactionInProgress = true;
@@ -342,7 +342,7 @@ void DatabaseBackend::scheduleTransaction()
 
 void DatabaseBackend::scheduleTransactionStep(SQLTransactionBackend* transaction)
 {
-    if (!databaseContext()->databaseThread())
+    if (!databaseContext()->databaseThread() || databaseContext()->databaseThread()->terminationRequested())
         return;
 
     OwnPtr<DatabaseTransactionTask> task = DatabaseTransactionTask::create(transaction);
@@ -913,7 +913,7 @@ Vector<String> DatabaseBackend::tableNames()
     // this may not be true anymore.
     Vector<String> result;
     TaskSynchronizer synchronizer;
-    if (!databaseContext()->databaseThread() || databaseContext()->databaseThread()->terminationRequested(&synchronizer))
+    if (!databaseContext()->databaseThread() || databaseContext()->databaseThread()->terminationRequested())
         return result;
 
     OwnPtr<DatabaseTableNamesTask> task = DatabaseTableNamesTask::create(this, &synchronizer, result);