regression in C-x v = in latest versions

[Paul Pogonyshev]

Hi,

With latest Emacs versions (yesterday SVN) I get very annoying behaviour
of C-x v = on SVN repository.  Now it doesn't use offline SVN copy of
modified files anymore, instead it always asks the server to diff.

E.g.  I open up an SVN-managed file, and type C-o C-x v =.  Previously,
I'd get instant difference of one added empty line, against offline
clean copy.  Now instead I get

        Running svn diff -r NNN FILENAME in the background...

in the echo area.  I guess the problem is in specifying the exact
revision number.

Paul