Reland "Update mojo Decryptor interface to support reusing shared memory"

media/mojo/services/mojo_decryptor.h

Index: media/mojo/services/mojo_decryptor.h
diff --git a/media/mojo/services/mojo_decryptor.h b/media/mojo/services/mojo_decryptor.h
index 131c0d0ac570f715c4433da622466f001b5a99cf..b8c0dab7cbbd24f921fb6974b7099a18ed5f63df 100644
--- a/media/mojo/services/mojo_decryptor.h
+++ b/media/mojo/services/mojo_decryptor.h
@@ -57,6 +57,10 @@ class MojoDecryptor : public Decryptor {
                       interfaces::Decryptor::Status status,
                       interfaces::VideoFramePtr video_frame);
 
+  // Called when done with a VideoFrame in order to reuse the shared memory.
+  void ReleaseSharedBuffer(mojo::ScopedSharedBufferHandle buffer,
+                           size_t buffer_size);
+
   // To pass DecoderBuffers to and from the MojoDecryptorService, 2 data pipes
   // are required (one each way). At initialization both pipes are created,
   // and then the handles are passed to the MojoDecryptorService.