shadow-dom: Added tests that checks matching order of CSS rules with @host

Added tests of matching order of CSS rules for @host.
This tests is related to the '@host @-rule' sections of the specs.
http://www.w3.org/TR/shadow-dom/#host-at-rule
Fixed indent style and performance improvement #189

Reflects the comment of the review of PR #189
shadow-dom: Fixed the title of test #189
Merge pull request #189 from summerwind/submission/matching-order

shadow-dom: Added tests that checks matching order of CSS rules with @host