2 files changed, 22 insertions, 4 deletions
diff --git a/webkit/quota/quota_task.cc b/webkit/quota/quota_task.cc
index 78a8b36..1f25ddf 100644
--- a/webkit/quota/quota_task.cc
+++ b/webkit/quota/quota_task.cc
@@ -67,9 +67,17 @@ void QuotaThreadTask::Run() {
 
 void QuotaThreadTask::CallRunOnTargetThread() {
   DCHECK(target_message_loop_->BelongsToCurrentThread());
+  if (RunOnTargetThreadAsync())
+    original_message_loop()->PostTask(
+        FROM_HERE, NewRunnableMethod(this, &QuotaThreadTask::CallCompleted));
+}
+
+bool QuotaThreadTask::RunOnTargetThreadAsync() {
   RunOnTargetThread();
-  original_message_loop()->PostTask(
-      FROM_HERE, NewRunnableMethod(this, &QuotaThreadTask::CallCompleted));
+  return true;
+}
+
+void QuotaThreadTask::RunOnTargetThread() {
 }
 
 // QuotaTaskObserver -------------------------------------------------------
diff --git a/webkit/quota/quota_task.h b/webkit/quota/quota_task.h
index 860ec0d..6b56593 100644
--- a/webkit/quota/quota_task.h
+++ b/webkit/quota/quota_task.h
@@ -66,8 +66,18 @@ class QuotaThreadTask : public QuotaTask,
  protected:
   virtual ~QuotaThreadTask();
 
-  // Called on the target message loop.
-  virtual void RunOnTargetThread() = 0;
+  // One of the following Run methods should be overriden for execution
+  // on the target thread.
+
+  // A task to invoke the CallCompleted() method on the original thread will
+  // be scheduled immediately upon return from RunOnTargetThread().
+  virtual void RunOnTargetThread();
+
+  // A task to invoke the CallCompleted() method on the original thread will
+  // only be scheduled if RunOnTargetThreadAsync returns true. If false is
+  // returned, the derived class should schedule a task to do so upon actual
+  // completion.
+  virtual bool RunOnTargetThreadAsync();
 
   virtual void Run() OVERRIDE;
   scoped_refptr<base::MessageLoopProxy> target_message_loop() const {