Unable to use java.io.File payload with file transport

• User impact:

  Medium
• Similar Issues:

  None

When using streaming FileMessageAdaptor with a FileInputStream payload is used by default.

When not using streaming FileContentsMessageAdaptor is used with a byte[] payload is used by default.

Since work on the file transport to make streaming work correctly it is no longer possible to pass a java.io.File payload.

We either need to:
i) Create a 3rd message adaptor for this case (which I suppose would only be used when overriding defaults)
ii) Make the FileMessageAdaptor a bit more intelligent so if it is created with a File getPayload() returns a file, and it is was created with a FileInputStream it returns a FileInputStream when getPayload() is called.