Generate enum/getters/setters/mappings for resize

Currently, the resize property is a 'storage_only' field, so
it has no generated public getters/setters.

This patch changes it to a 'keyword' field so that its getters/setters
can be generated as well. We also generate the EResize enum and
use the generated CSSValueID <-> EResize mappings.

Diff: https://gist.github.com/nainar/de2cc565a04bae3e08b4ab5df1c981a7/revisions

BUG=628043

Change-Id: I939599a958396b2dc2e056afbe3d7bfe2207e4ff
Reviewed-on: https://chromium-review.googlesource.com/536573
Commit-Queue: nainar <nainar@chromium.org>
Reviewed-by: Darren Shen <shend@chromium.org>
Cr-Commit-Position: refs/heads/master@{#480330}
5 files changed