1;2305;0cRevert 86971 - Move media library AutoTaskRunner to base and rename ScopedTaskRunner.

media/base/callback.h

Index: media/base/callback.h
===================================================================
--- media/base/callback.h	(revision 86971)
+++ media/base/callback.h	(working copy)
@@ -4,9 +4,9 @@
 
 // Some basic utilities for aiding in the management of Tasks and Callbacks.
 //
-// AutoCallbackRunner is akin to scoped_ptr for callbacks.  It is useful for
-// ensuring a callback is executed and delete in the face of multiple return
-// points in a function.
+// AutoTaskRunner, and its brother AutoCallbackRunner are the scoped_ptr
+// equivalents for callbacks.  They are useful for ensuring a callback is
+// executed and delete in the face of multiple return points in a function.
 //
 // TaskToCallbackAdapter converts a Task to a Callback0::Type since the two type
 // hierarchies are strangely separate.
@@ -27,6 +27,23 @@
 
 namespace media {
 
+class AutoTaskRunner {
+ public:
+  // Takes ownership of the task.
+  explicit AutoTaskRunner(Task* task)
+      : task_(task) {
+  }
+
+  ~AutoTaskRunner();
+
+  Task* release() { return task_.release(); }
+
+ private:
+  scoped_ptr<Task> task_;
+
+  DISALLOW_COPY_AND_ASSIGN(AutoTaskRunner);
+};
+
 class AutoCallbackRunner {
  public:
   // Takes ownership of the callback.
@@ -60,6 +77,38 @@
   DISALLOW_COPY_AND_ASSIGN(TaskToCallbackAdapter);
 };
 
+template <typename CallbackType>
+class CleanupCallback : public CallbackType {
+ public:
+  explicit CleanupCallback(CallbackType* callback) : callback_(callback) {}
+
+  virtual ~CleanupCallback() {
+    for (size_t i = 0; i < run_when_done_.size(); i++) {
+      run_when_done_[i]->Run();
+      delete run_when_done_[i];
+    }
+  }
+
+  virtual void RunWithParams(const typename CallbackType::TupleType& params) {
+    callback_->RunWithParams(params);
+  }
+
+  template <typename T>
+  void DeleteWhenDone(T* ptr) {
+    RunWhenDone(new DeleteTask<T>(ptr));
+  }
+
+  void RunWhenDone(Task* ptr) {
+    run_when_done_.push_back(ptr);
+  }
+
+ private:
+  scoped_ptr<CallbackType> callback_;
+  std::vector<Task*> run_when_done_;
+
+  DISALLOW_COPY_AND_ASSIGN(CleanupCallback);
+};
+
 }  // namespace media
 
 #endif  // MEDIA_BASE_CALLBACK_