WebSQL: Add missing getExecutionContext() null check

third_party/WebKit/Source/modules/webdatabase/Database.cpp

Index: third_party/WebKit/Source/modules/webdatabase/Database.cpp
diff --git a/third_party/WebKit/Source/modules/webdatabase/Database.cpp b/third_party/WebKit/Source/modules/webdatabase/Database.cpp
index bb50d592b9c1637ac31a200d13f7dd3845365692..b23113b215a4705cc90a4265d024cccd9121416e 100644
--- a/third_party/WebKit/Source/modules/webdatabase/Database.cpp
+++ b/third_party/WebKit/Source/modules/webdatabase/Database.cpp
@@ -851,6 +851,9 @@ void Database::runTransaction(SQLTransactionCallback* callback,
                               VoidCallback* successCallback,
                               bool readOnly,
                               const ChangeVersionData* changeVersionData) {
+  if (!getExecutionContext())
+    return;
+
   ASSERT(getExecutionContext()->isContextThread());
 // FIXME: Rather than passing errorCallback to SQLTransaction and then
 // sometimes firing it ourselves, this code should probably be pushed down