Remove unnecessary recalc of host subtree on distribute.

Nodes which need style recalculations after being distributed to new
insertion points, new positions within insertion points, or simply not
distributed anymore, are being reattached in
InsertionPoint::setDistributionNodes().

R=hayato@chromium.org,kochi@chromium.org,esprehn@chromium.org
TEST=fast/dom/shadow,fast/css
BUG=584177

Review URL: https://codereview.chromium.org/1677463002

Cr-Commit-Position: refs/heads/master@{#374629}
3 files changed