Add support for svn 1.4 to trychange.py

Add support for svn 1.4 to trychange.py

svn 1.4 doesn't have --depth parameter support so it cannot easily do a sparse checkout.

To workaround that, use svn import instead. It's also faster.
The main caveat is that the file must have a unique name, it uses a timestamp in file name for uniqueness.

Using a subdirectory (like the user name) doesn't work in the directory already exist.

It could be worked around but that would nullify the performance improvement.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=45811

[Nicolas Sylvain, 2010-04-28 14:34:43]

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