Use generated copy and compare for VerticalAlign in ComputedStyle.

The vertical_align_ field in ComputedStyle currently has generated
storage, but not copy and compare. This patch makes it use generated
copy and compare. We are able to do this now because we have added
the 'has_custom_compare_and_copy' parameter in a previous patch.

Diff of generated files:
https://gist.github.com/183fa3073f5de347a685b1834913ee2e/revisions

BUG=628043

Review-Url: https://codereview.chromium.org/2834583004
Cr-Commit-Position: refs/heads/master@{#467874}
2 files changed