Always call UpdateCompositedScrollOffset, not just for the root layer

Bug: 927560
Change-Id: I1d5522aae4f11dd3f5b8947bb089bac1bf19bdb4
Reviewed-on: https://chromium-review.googlesource.com/c/1452701
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Commit-Queue: Mason Freed <masonfreed@chromium.org>
Cr-Commit-Position: refs/heads/master@{#628942}
void PaintLayerScrollableArea::PreventRelayoutScope::SetBoxNeedsLayout(
    PaintLayerScrollableArea& scrollable_area,
    bool had_horizontal_scrollbar,
    bool had_vertical_scrollbar) {
  DCHECK(count_);
  DCHECK(layout_scope_);
  if (scrollable_area.NeedsRelayout())
    return;
  scrollable_area.SetNeedsRelayout(true);
  scrollable_area.SetHadHorizontalScrollbarBeforeRelayout(
      had_horizontal_scrollbar);
  scrollable_area.SetHadVerticalScrollbarBeforeRelayout(had_vertical_scrollbar);

  relayout_needed_ = true;
  NeedsRelayoutList().push_back(&scrollable_area);
}

void PaintLayerScrollableArea::PreventRelayoutScope::SetBoxNeedsLayout(
    PaintLayerScrollableArea& scrollable_area,
    bool had_horizontal_scrollbar,
    bool had_vertical_scrollbar) {
  DCHECK(count_);
  DCHECK(layout_scope_);
  if (scrollable_area.NeedsRelayout())
    return;
  scrollable_area.SetNeedsRelayout(true);
  scrollable_area.SetHadHorizontalScrollbarBeforeRelayout(
      had_horizontal_scrollbar);
  scrollable_area.SetHadVerticalScrollbarBeforeRelayout(had_vertical_scrollbar);

  relayout_needed_ = true;
  NeedsRelayoutList().push_back(&scrollable_area);
}
