Support animations and transitions for vertical-align

The property vertical-align is listed (by css-transitions) as animatable
but we don't currently support animating it. This patch adds support for
it, which also reduces the number of failures on the following w3c tests
for transitions:
- properties-value-implicit-001
- properties-value-inherit-002
- properties-value-inherit-001
- properties-value-001

BUG=375098

Review URL: https://codereview.chromium.org/296133005

git-svn-id: svn://svn.chromium.org/blink/trunk@174598 bbb929c8-8fbe-4397-9dbb-9b2b20218538