Moved nonproperty isLink to be generated in ComputedStyleBase.

Move the nonproperty field isLink to be generated in ComputedStyleBase.
Also moved getter / setter methods to be generated in ComputedStyleBase.

Diff: https://gist.github.com/76592244b306fb4f5c953e0f67687d53/revisions

BUG=628043

Review-Url: https://codereview.chromium.org/2657423004
Cr-Commit-Position: refs/heads/master@{#456948}
2 files changed