Enable the ability to run layout tests on Vista as well as XP. See the note ...

Enable the ability to run layout tests on Vista as well as XP. See the note 
sent to chromium-dev for more info. This change changes test_shell to use
--generic-theme when --layout-tests is specified. Also, two new platform
directories have been added for baselines, chromium-win-xp and 
chromium-win-vista. chromium-win-vista should be empty (it just needs to
exist for run_webkit_tests.py to function properly), and chromium-win-xp
should contain only XP-specific baselines.

In addition to this change, we will commit a new set of baselines directly
using svn (rather than going through Rietveld).

  R=TBD
  BUG=none
  TEST=none


Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=26203

[darin (slow to review), 2009-09-15 16:23:57]

http://codereview.chromium.org/203065/diff/1/3
File webkit/tools/layout_tests/layout_package/platform_utils_win.py (right):

http://codereview.chromium.org/203065/diff/1/3#newcode25
Line 25: elif winver[0] == 5 and (winver[1] == 1 or winver[1] == 2):
nit: no need for else after return.  just do "if" instead of "elif"

http://codereview.chromium.org/203065/diff/1/2
File webkit/tools/layout_tests/test_expectations.txt (right):

http://codereview.chromium.org/203065/diff/1/2#newcode2335
Line 2335: BUG21859 WIN-XP : LayoutTests/fast/text/line-breaks.html = FAIL
it seems strange that we would regress XP behavior.  what happened there?