[Remoting Android] JniGlDisplayHandler calls invalidate() on UI thread

remoting/client/jni/display_updater_factory.h

 // Copyright 2016 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef REMOTING_CLIENT_JNI_DISPLAY_UPDATER_FACTORY_H_
 #define REMOTING_CLIENT_JNI_DISPLAY_UPDATER_FACTORY_H_
 
 #include <memory>
 
 #include "base/macros.h"
 
 namespace remoting {
 
 namespace protocol {
 class CursorShapeStub;
 class VideoRenderer;
 }  // namespace protocol
 
 // Interface for creating objects to update image (desktop frame or cursor
 // shape) to display. Factory functions can be called on any thread but the
 // returned object should be used on the network thread.
 class DisplayUpdaterFactory {

[Hzj_jie, 2016/09/13 19:32:12]

Will this class be removed eventually? It looks like JniGlDisplayHandler is the
only consumer.

[Yuwei, 2016/09/13 20:49:40]

I'm thinking about removing this class but just not sure whether there will be a
different RenderStub (VR?) in the future...

  public:
-  virtual ~DisplayUpdaterFactory() {}
+  // A deleter that calls Destroy() to delete the factory.
+  struct Deleter {
+    void operator()(DisplayUpdaterFactory* factory) {

[Hzj_jie, 2016/09/13 19:32:12]

if (factory) {
  factory->Destroy();
}

I happen to find a doc regarding to the deleter of smart pointers.
http://stackoverflow.com/questions/11164354/does-the-standard-behavior-for-de....
So this deleter may be called even with a nullptr in shared_ptr.

[Yuwei, 2016/09/13 20:49:40]

Added the null-check.

+      factory->Destroy();
+    }
+  };
 
   virtual std::unique_ptr<protocol::CursorShapeStub>
   CreateCursorShapeStub() = 0;
   virtual std::unique_ptr<protocol::VideoRenderer> CreateVideoRenderer() = 0;
 
+  // Destroys the factory object and frees the memory.
+  virtual void Destroy() = 0;
+
  protected:
+  virtual ~DisplayUpdaterFactory() {}
   DisplayUpdaterFactory() {}
 
  private:
   DISALLOW_COPY_AND_ASSIGN(DisplayUpdaterFactory);
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_CLIENT_JNI_DISPLAY_UPDATER_FACTORY_H_