[chromium] Fix ietestcenter/css3/bordersbackgrounds/border-radius-clip-002.htm expectation lines

Unreviewed gardening.

* platform/chromium/TestExpectations: Two bugs and expectation lines refer to this test, and one
expectation line overrides the other: assign to the earlier bug and ditch the redundant line.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@139307 268f45cc-cd09-0410-ab3c-d52691b4dbfc