Revert 194990 "Second take at handling users with locally overri..."

Revert 194990 "Second take at handling users with locally overri..."

> Second take at handling users with locally overridden diff-cmds.
> 
> The first take at https://chromiumcodereview.appspot.com/14130006 tried to pass
> "--diff-cmd diff", which doesn't work for e.g. Windows cmd users who don't have
> a "diff" executable installed.
> 
> This take instead passes the "--internal-diff" switch which tells svn to ignore
> any diff-cmd set locally and use its internal diff engine at all times.
> 
> While implementing this I found that the existing code tried to work around this
> problem in a different way, by setting up a bogus config dir.  Since that
> doesn't seem to work for me, and shouldn't be necessary with this patch anyway,
> removed that code.
> 
> Review URL: https://chromiumcodereview.appspot.com/14050007

TBR=pkasting@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=195009

[Peter Kasting, 2013-04-18 21:38:43]

Committed patchset #1 manually as r195009.