check-webkit-style can't handle qt-arm, qt-win, qt-mac, qt-5.0, qt-5.0-wk1 and qt-5.0-wk2 TestExpecatations
https://bugs.webkit.org/show_bug.cgi?id=98140

Reviewed by Eric Seidel.

Fix a bug where we were always using the host OS rather than using what was passed in as part of the
port name on Qt.

There's also a bug with being able to test for qt-5.0 expectations files when on a system with
Qt 4.8 installed. I'm not sure how to solve that, so for now, stop emitting a style warning about
not checking a file.

* Scripts/webkitpy/layout_tests/port/qt.py:
(QtPort._search_paths): Use passed in OS.
* Scripts/webkitpy/style/checkers/test_expectations.py:
(TestExpectationsChecker.check): Don't warn if we don't know about the TestExpectations file.
* Scripts/webkitpy/style/checkers/test_expectations_unittest.py:
(TestExpectationsTestCase.test_determine_port_from_expectations_path): Added a test case for the OS fix.
Add a commented out test for the version case.


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@130220 268f45cc-cd09-0410-ab3c-d52691b4dbfc