Oilpan: Prepare to move DatabaseThread and SQLTransactionCoordinator to Oilpan heap.

Source/modules/webdatabase/SQLTransactionCoordinator.cpp

Index: Source/modules/webdatabase/SQLTransactionCoordinator.cpp
diff --git a/Source/modules/webdatabase/SQLTransactionCoordinator.cpp b/Source/modules/webdatabase/SQLTransactionCoordinator.cpp
index b81ee2457b5e6f7eff768724fc3a56e34315f7f6..75b59a8796a098b278c9cf761e70d65694a57f46 100644
--- a/Source/modules/webdatabase/SQLTransactionCoordinator.cpp
+++ b/Source/modules/webdatabase/SQLTransactionCoordinator.cpp
@@ -49,6 +49,11 @@ SQLTransactionCoordinator::SQLTransactionCoordinator()
 {
 }
 
+void SQLTransactionCoordinator::trace(Visitor* visitor)
+{
+    visitor->trace(m_coordinationInfoMap);
+}
+
 void SQLTransactionCoordinator::processPendingTransactions(CoordinationInfo& info)
 {
     if (info.activeWriteTransaction || info.pendingTransactions.isEmpty())