Fix ChromotingHost and DesktopEnvironmentFactory references to TaskRunners.

remoting/host/desktop_environment_factory.h

 // Copyright (c) 2012 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_HOST_DESKTOP_ENVIRONMENT_FACTORY_H_
 #define REMOTING_HOST_DESKTOP_ENVIRONMENT_FACTORY_H_
 
 #include "base/basictypes.h"
+#include "base/memory/ref_counted.h"
 #include "base/memory/scoped_ptr.h"
 
+namespace base {
+class SingleThreadTaskRunner;
+}  // namespace base
+
 namespace remoting {
 
-class ChromotingHostContext;
 class DesktopEnvironment;
 
 class DesktopEnvironmentFactory {
  public:
-  DesktopEnvironmentFactory();
+  DesktopEnvironmentFactory(
+      scoped_refptr<base::SingleThreadTaskRunner> input_task_runner,
+      scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner);
   virtual ~DesktopEnvironmentFactory();
 
-  virtual scoped_ptr<DesktopEnvironment> Create(
-      ChromotingHostContext* context);
+  virtual scoped_ptr<DesktopEnvironment> Create();
 
   // Returns |true| if created |DesktopEnvironment| instances support audio
   // capture.
   virtual bool SupportsAudioCapture() const;
 
  protected:
+  scoped_refptr<base::SingleThreadTaskRunner> input_task_runner_;

[alexeypa (please no reviews), 2012/10/01 18:31:34]

Now that you have these pointers here, you will need to make sure that
DesktopEnvironmentFactory is deleted as part of the host shutdown. There are at
least three different places: me2me host, simple host, and it2me host. I'm not
sure about unit tests.

Passing the task runners to Create() is less elegant but it helps to avoid this
problem, because the references will be released when a desktop environment
instance if deleted.

[Wez, 2012/10/02 05:19:44]

Good point; I've updated things to destroy the DesktopEnvironmentFactory when
the shutdown task is invoked, for the most part.  ChromotingHost can actually
queue up multiple callbacks, though, which is something else I think we should
clean up.

The ordering constraint will go away once we move the threads into
DesktopEnvironmentFactory itself.

+  scoped_refptr<base::SingleThreadTaskRunner> ui_task_runner_;
+
   DISALLOW_COPY_AND_ASSIGN(DesktopEnvironmentFactory);
 };
 
 }  // namespace remoting
 
 #endif  // REMOTING_HOST_DESKTOP_ENVIRONMENT_FACTORY_H_