[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 {

[Sergey Ulanov, 2016/09/19 21:14:56]

Do we need to keep this interface? I think we needed it to support two
capturers, but I don't think we will need this going forward, so maybe we can
just remove it?

[Yuwei, 2016/09/19 23:52:10]

That's what I have considered. Removed.

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

[Lambros, 2016/09/16 01:44:12]

Does it make sense for this deleter (and Destroy method) to be here in the
interface, instead of in JniGlDisplayHandler?

[Yuwei, 2016/09/16 21:49:44]

I don't have a strong opinion. My justifications are:

1. Anyone who needs to create a reset-able unique_ptr will need such a deleter
2. Currently JniClient references to the DisplayHandler as the interface so
Destroy() probably can't be removed from the interface. Also arguably it may be
good if any future renderer implementations can have a chance to handle the
destroy process by itself.

+  struct Deleter {
+    void operator()(DisplayUpdaterFactory* factory) {
+      if (factory) {
+        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_