Simplify -webkit-line-box-contain parsing
Simplify -webkit-line-box-contain parsing

This patch reduces code duplication a little in -webkit-line-box-contain parsing.

Review URL: https://codereview.chromium.org/429803004

git-svn-id: bf5cd6ccde378db821296732a091cfbcf5285fbd@179383 bbb929c8-8fbe-4397-9dbb-9b2b20218538

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