Update style for child SVG documents in PerformPreLayoutTasks

Like in LocalFrameView::UpdateStyleAndLayoutIfNeededRecursive,
explicitly update style (and attach the layout tree) before proceeding
to layout. This ensures that the style update/layout tree attachment of
the child document does not mark its frame owner as dirty after layout
has already been performed for the top-level document.

Bug: 933409
Change-Id: I6b2c864aededed7429c63cbd068ec45c58972ae0
Reviewed-on: https://chromium-review.googlesource.com/c/1481331
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Commit-Queue: Fredrik Söderquist <fs@opera.com>
Cr-Commit-Position: refs/heads/master@{#635459}
2 files changed