Fix RectangleUpdateDecoder to reference the FrameConsumerProxy.

RectangleUpdateDecoder runs on a separate thread from the FrameConsumer in the PPAPI plugin client, requiring FrameConsumer calls to be proxied to the correct thread.  Previously it was passed a bare FrameConsumer pointer, with the underlying FrameConsumerProxy lifetime managed by the ChromotingInstance.  Since the RectangleUpdateDecoder is itself ref-counted it can outlive the ChromotingInstance, and thereby the FrameConsumerProxy, if it is still processing queued messages at the time.

This CL:
* Changes RectangleUpdateDecoder() to take scoped_refptr<>s to the message-loop-proxy and consumer.
* Has RectangleUpdateDecoder() take a FrameConsumerProxy, since FrameConsumer is not ref-counted.  Ideally it should take a scoped_ptr<FrameConsumer>, and leave ref-counting to be an internal detail of FrameConsumerProxy. 

Also:
* FrameConsumerProxy now accepts a WeakPtr<FrameConsumer>, removing the need for an explicit Detach(), which feels safer.  The WeakPtr must have been created on the thread the FrameConsumerProxy will punt calls to, which shouldn't be a problem.
* PepperView now SupportsWeakPtr rather than containing a WeakPtrFactory, to make it easy to get a WeakPtr to it.

BUG=118110


Review URL: http://codereview.chromium.org/9703006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@127035 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 5 insertions, 8 deletions

diff --git a/remoting/client/frame_consumer_proxy.h b/remoting/client/frame_consumer_proxy.h
index 039f042..7e62f2e 100644
--- a/remoting/client/frame_consumer_proxy.h
+++ b/remoting/client/frame_consumer_proxy.h
@@ -11,6 +11,7 @@
 #define REMOTING_CLIENT_FRAME_CONSUMER_PROXY_H_
 
 #include "base/memory/ref_counted.h"
+#include "base/memory/weak_ptr.h"
 #include "remoting/client/frame_consumer.h"
 
 namespace base {
@@ -25,7 +26,8 @@ class FrameConsumerProxy
  public:
   // Constructs a proxy for |frame_consumer| which will trampoline invocations
   // to |frame_consumer_message_loop|.
-  FrameConsumerProxy(base::MessageLoopProxy* frame_consumer_message_loop);
+  FrameConsumerProxy(
+      scoped_refptr<base::MessageLoopProxy> frame_consumer_message_loop);
   virtual ~FrameConsumerProxy();
 
   // FrameConsumer implementation.
@@ -38,15 +40,10 @@ class FrameConsumerProxy
 
   // Attaches to |frame_consumer_|.
   // This must only be called from |frame_consumer_message_loop_|.
-  void Attach(FrameConsumer* frame_consumer);
-
-  // Detaches from |frame_consumer_|, ensuring no further calls reach it.
-  // This must only be called from |frame_consumer_message_loop_|.
-  void Detach();
+  void Attach(const base::WeakPtr<FrameConsumer>& frame_consumer);
 
  private:
-  FrameConsumer* frame_consumer_;
-
+  base::WeakPtr<FrameConsumer> frame_consumer_;
   scoped_refptr<base::MessageLoopProxy> frame_consumer_message_loop_;
 
   DISALLOW_COPY_AND_ASSIGN(FrameConsumerProxy);