Revert r190501 "Roll swarm_client @ 190463."

Revert r190501 "Roll swarm_client @ 190463."

It made many test fails to get the test case list and I failed to reproduce
locally.

TBR=csharp@chromium.org
BUG=
NOTRY=true

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=190512

[M-A Ruel, 2013-03-25 23:43:55]

For example
http://build.chromium.org/p/chromium.win/builders/Win%207%20Tests%20x64%20%28...
E:\b\depot_tools\python_bin\python_slave.exe
E:\b\build\slave\Win_7_Tests_x64__1_\build\src\build\..\tools\sharding_supervisor\sharding_supervisor.py
--no-color --retry-failed
E:\b\build\slave\Win_7_Tests_x64__1_\build\src\build\Release_x64\ppapi_unittests.exe
--gtest_print_time
--gtest_output=xml:gtest-results\ppapi_unittests\ppapi_unittests.xml
Note: This is test shard 1 of 1.
Found no test to run
No data was available to update the JSON results


or

http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%2...
/usr/bin/python ../../../scripts/slave/runisolatedtest.py --test_name
cacheinvalidation_unittests --builder_name "Linux ChromiumOS Tests (1)"
--tool_dir
/mnt/data/b/build/slave/Linux_ChromiumOS_Tests__1_/build/src/out/../tools
/mnt/data/b/build/slave/Linux_ChromiumOS_Tests__1_/build/src/out/Release/cacheinvalidation_unittests
-- /usr/bin/python
/mnt/data/b/build/slave/Linux_ChromiumOS_Tests__1_/build/src/out/../tools/sharding_supervisor/sharding_supervisor.py
--no-color --retry-failed
/mnt/data/b/build/slave/Linux_ChromiumOS_Tests__1_/build/src/out/Release/cacheinvalidation_unittests
--gtest_print_time
--gtest_output=xml:gtest-results/cacheinvalidation_unittests/cacheinvalidation_unittests.xml

/usr/bin/python
/mnt/data/b/build/slave/Linux_ChromiumOS_Tests__1_/build/src/out/../tools/sharding_supervisor/sharding_supervisor.py
--no-color --retry-failed
/mnt/data/b/build/slave/Linux_ChromiumOS_Tests__1_/build/src/out/Release/cacheinvalidation_unittests
--gtest_print_time
--gtest_output=xml:gtest-results/cacheinvalidation_unittests/cacheinvalidation_unittests.xml
Note: This is test shard 1 of 1.
Found no test to run
Stopping Xvfb with pid 4419 ...
Xvfb pid file removed
"/mnt/data/b/build/slave/Linux_ChromiumOS_Tests__1_/build" \
"gtest-results/cacheinvalidation_unittests/cacheinvalidation_unittests.xml"
doesn't exist: Unable to generate JSON from XML, using log output.
No data was available to update the JSON results

[M-A Ruel, 2013-03-25 23:45:57]

Committed patchset #1 manually as r190512.

[csharp, 2013-03-26 13:35:02]

lgtm