Incorporate BlobChannel into Blimp image encode/decode pipeline.

blimp/client/feature/compositor/client_image_serialization_processor.h

Index: blimp/client/feature/compositor/client_image_serialization_processor.h
diff --git a/blimp/client/feature/compositor/client_image_serialization_processor.h b/blimp/client/feature/compositor/client_image_serialization_processor.h
index 5118f428cf6b539e65cf1bc2dc03743a78c35f39..7caffc8573db980eecbc0fbf4a1972b6f297b8f6 100644
--- a/blimp/client/feature/compositor/client_image_serialization_processor.h
+++ b/blimp/client/feature/compositor/client_image_serialization_processor.h
@@ -5,29 +5,67 @@
 #ifndef BLIMP_CLIENT_FEATURE_COMPOSITOR_CLIENT_IMAGE_SERIALIZATION_PROCESSOR_H_
 #define BLIMP_CLIENT_FEATURE_COMPOSITOR_CLIENT_IMAGE_SERIALIZATION_PROCESSOR_H_
 
+#include <memory>
+
 #include "base/macros.h"
+#include "base/memory/singleton.h"
 #include "cc/proto/image_serialization_processor.h"
 #include "third_party/skia/include/core/SkPicture.h"
 
 class SkPixelSerializer;
 
 namespace blimp {
+
+class BlobChannelReceiver;
+
 namespace client {
 
-// ClientImageSerializationProcessor provides functionality to deserialize Skia
-// images.
+// Adds BlobChannel image retrieval support to the Skia image decoding process.
 class ClientImageSerializationProcessor
     : public cc::ImageSerializationProcessor {
  public:
+  class ErrorDelegate {
+   public:
+    virtual void OnImageDecodeError() = 0;
+  };
+
+  static ClientImageSerializationProcessor* GetInstance();
+
+  // Sets the |blob_receiver| to use for reading images.
+  // |blob_receiver| must outlive |this|.
+  void set_blob_receiver(BlobChannelReceiver* blob_receiver) {
+    blob_receiver_ = blob_receiver;
+  }
+
+  // |error_delegate| must outlive this.
+  void set_error_delegate(ErrorDelegate* error_delegate) {
+    error_delegate_ = error_delegate;
+  }
+
+  // Retrieves a bitmap with ID |input| from |blob_receiver_| and decodes it
+  // to |bitmap|.
+  bool GetAndDecodeBlob(const void* input, size_t input_size, SkBitmap* bitmap);
+
+ private:
+  friend struct base::DefaultSingletonTraits<ClientImageSerializationProcessor>;
+
   ClientImageSerializationProcessor();
-  ~ClientImageSerializationProcessor();
+  virtual ~ClientImageSerializationProcessor();
 
-  // cc::ImageSerializationProcessor implementation.
+  // Adapts a bare function pointer call to a singleton call to
+  // GetAndDecodeBlob().
+  static bool InstallPixelRefProc(const void* input,
+                                  size_t input_size,
+                                  SkBitmap* bitmap);
+
+  // cc:ImageSerializationProcessor implementation.
   SkPixelSerializer* GetPixelSerializer() override;
   SkPicture::InstallPixelRefProc GetPixelDeserializer() override;
 
- private:
-  SkPicture::InstallPixelRefProc pixel_deserializer_;
+  // Interface for accessing stored images received over the Blob Channel.
+  BlobChannelReceiver* blob_receiver_ = nullptr;
+
+  ErrorDelegate* error_delegate_ = nullptr;
 
   DISALLOW_COPY_AND_ASSIGN(ClientImageSerializationProcessor);
 };