Use PARCELABLE_WIRTE_RETURN_VALUE flag in InputChannel.

Bug: 5161290

Replace mDisposeAfterWriteToParcel with code that takes advantage
of the standard Parcel API support for releasing resources after
writing a Binder reply.

This change makes it less likely that InputChannels will leak
accidentally when passed across a Binder.

Change-Id: Id37706e7b88d074e8e4ac687c88f0db8963200f2