Remove incorrect styleResolver() checks.

Whether the StyleResolver is created or not does no longer tell if we
have usable invalidation sets or not. Removing SubtreeStyleChange which
is presumably not necessary anymore.

Add a check for not scheduling any invalidation sets if the document is
already marked for full recalc.

Review-Url: https://codereview.chromium.org/2749273004
Cr-Commit-Position: refs/heads/master@{#457383}
3 files changed