[ANSI-Smalltalk] #contents on WriteStream

[Paolo Bonzini]

In the standard, the definition of #contents for <WriteStream> comes
from <collectionStream> so that this:

   (WriteStream on: String new) nextPutAll: 'abc'; skip: -1;
      contents

should "return a collection that contains the receiver's past and future
sequence values, in order", i.e. 'abc'.  To me it makes more sense that
it returns 'ab'.

Opinions?

Paolo