[chromium] Remove lost-compositor-context layout tests
https://bugs.webkit.org/show_bug.cgi?id=106089

Unreviewed gardening.

* platform/chromium/TestExpectations: Remove all references to the
lost-compositor-context test expectations after r138814.

git-svn-id: http://svn.webkit.org/repository/webkit/trunk@139304 268f45cc-cd09-0410-ab3c-d52691b4dbfc