Apply a minor performance tweak in ra_svn's blame handler that is also implemented in the other ra layers: avoid work when the txdelta is ignored by using the standard noop handler to receive all windows.
Apply a minor performance tweak in ra_svn's blame handler that is also
implemented in the other ra layers: avoid work when the txdelta is ignored
by using the standard noop handler to receive all windows.

* subversion/libsvn_ra_svn/client.c
  (ra_svn_get_file_revs): Don't create a stream when the handler is the
    explicit noop window handler, as that will not use the data anyway.


git-svn-id: f8a4e5e023278da1e04e203c7fe051e3c4285d88@1503046 13f79535-47bb-0310-9956-ffa450edef68

YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion,YueLinHo/Subversion