cancel_transition is flaky on Linux debug as well. Mark it as such. 
cancel_transition is flaky on Linux debug as well. Mark it as such. 

TBR=dglazkov
BUG=15627 (http://crbug.com/15627)
TEST=Linux webkit (debug) does not report cancel-transition as a failure

Review URL: http://codereview.chromium.org/147134

git-svn-id: dd90618784b6a4b323ea0c23a071cb1c9e6f2ac7@19226 4ff67af0-8c30-449e-8e8b-ad334ec8d88c

wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser,wistoch/meego-app-browser