[css-writing-modes] Remove interaction of text-combine-horizontal and font-variant: full-width per <http://lists.w3.org/Archives/Public/www-style/2013Sep/0091.html>

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extra : rebase_source : 499453995aee9cb5a402694d5180d9f06f89d5a2
[css-ruby] Add more explanation for ruby-merge: auto, and check in missing image.

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extra : rebase_source : 19e57434c064bcda03a20345fa6e4615a2f4f8fa