css-writing-modes-3: add parsing tests for text-combine-upright.

there are four files:

* text-combine-upright-parsing-valid-001.html : test cases for valid values
* text-combine-upright-parsing-valid-002.html : test cases for valid values using calc()
* text-combine-upright-parsing-invalid-001.html : test cases for invalid values
* text-combine-upright-parsing-invalid-002.html : test cases for invalid values using calc()
fix the syntax of flags.
Merge pull request #554 from myakura/myakura/text-combine-upright-parsing

LGTM. About calc() function, We have discussed with fantasai.