Revert 240460 "Roll swarm_client @ 9fc05789e3."

Revert 240460 "Roll swarm_client @ 9fc05789e3."

Speculative revert because base_unittests and net_unittests are failing
on almost all of the Windows builders, with errors like:

[------ Swarming Error ------]
Input file E:\b\build\slave\Win7_Tests__3_\build\src\build\Release\chrome_100_percent.pak doesn't exist

> Roll swarm_client @ 9fc05789e3.
>
> Includes revert of r240243.
>
> $ git log aab3a62beb..9fc05789e3 --date=short --format="%ad %ae %s" | sed 's/@chromium\.org//'
> 2013-12-11 ganetsky Create a .gitignore file and add *.pyc to it
> 2013-12-11 maruel Stop signalling swarming error on Windows file locking.
> 2013-12-11 maruel Ensure variables are decoded to unicode.
> 2013-12-06 maruel Rename --command-variable to --extra-variables.
> 2013-12-06 maruel Add real variable support and split --variable in 3 different flags.
> 2013-12-05 vadimsh Add 'offset' parameter to StorageApi.fetch(...) method.
> 2013-12-05 maruel Change log message to be clearer.
> 2013-12-05 vadimsh Support custom HTTP headers in net.url_open.
> 2013-12-03 vadimsh Remove urllib2 support.
> 2013-12-03 vadimsh Wait for Storage's internal threads to finish before exiting.
> 2013-12-03 vadimsh Fix swarming_smoke_test.py and isolateserver_test.py.
>
> R=vadimsh@chromium.org
> NOTRY=true
> BUG=
>
> Review URL: https://codereview.chromium.org/113553003

TBR=maruel@chromium.org

Review URL: https://codereview.chromium.org/101143003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@240528 0039d316-1c4b-4281-b951-d872f2087c98