Incorporate BlobChannel into Blimp image encode/decode pipeline.

blimp/client/feature/compositor/blimp_compositor_manager.h

Index: blimp/client/feature/compositor/blimp_compositor_manager.h
diff --git a/blimp/client/feature/compositor/blimp_compositor_manager.h b/blimp/client/feature/compositor/blimp_compositor_manager.h
index d4e1ec2177253864e8aa900f307892ecba823f47..9c4b92277cd1419b3098609b50c34c4f8881eaa0 100644
--- a/blimp/client/feature/compositor/blimp_compositor_manager.h
+++ b/blimp/client/feature/compositor/blimp_compositor_manager.h
@@ -5,6 +5,8 @@
 #ifndef BLIMP_CLIENT_FEATURE_COMPOSITOR_BLIMP_COMPOSITOR_MANAGER_H_
 #define BLIMP_CLIENT_FEATURE_COMPOSITOR_BLIMP_COMPOSITOR_MANAGER_H_
 
+#include <map>
+
 #include "base/macros.h"
 #include "blimp/client/feature/compositor/blimp_compositor.h"
 #include "blimp/client/feature/compositor/blimp_gpu_memory_buffer_manager.h"
@@ -93,9 +95,8 @@ class BlimpCompositorManager
 
   std::unique_ptr<BlimpGpuMemoryBufferManager> gpu_memory_buffer_manager_;
 
-  // Provides the functionality to deserialize images in SkPicture.
-  std::unique_ptr<ClientImageSerializationProcessor>
-      image_serialization_processor_;
+  // Retrieves and decode images from the BlobChannel.
+  ClientImageSerializationProcessor* image_serialization_processor_;

[nyquist, 2016/06/03 18:30:44]

Nit: Do we want to mention any thing about this being a singleton here, to
clarify the lifetime of the object?

[Kevin M, 2016/06/06 17:43:38]

I'm not sure if that's necessary, given that the variable is bound inside the
module instead of being taken from a caller. IMO lifetime constraints are more
important if they are a part of the public interface, so that the object owner
knows to handle the object lifetimes properly.

If you feel strongly I can still document it, but I'm just explaining my
rationale. :)

[nyquist, 2016/06/06 21:10:46]

Nah, I agree.

 
   // A map of render_widget_ids to the BlimpCompositor instance.
   typedef std::map<int, std::unique_ptr<BlimpCompositor>> CompositorMap;