[BlinkGenPropertyTrees] Stop setting three cc::Layer positioning values

This patch stops setting and using the following positioning values with
BlinkGenPropertyTrees because they were only needed for the cc property
tree builder:
  is_resized_by_browser_controls
  is_container_for_fixed_position_layers
  position_constraint

This has the potential to be a performance benefit because some
unnecessary cc::Layer::SetNeedsCommit calls have been removed in the
BlinkGenPropertyTrees codepath. This also stops calling
Layer::DescendantIsFixedToContainerLayer and
ScrollingCoordinator::ComputePositionConstraint which are both
O(|layers|^2).

Bug: 836886
Change-Id: Id3e2cb56b8a1eee69e39e3bf44c527cb915216bc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1528478
Commit-Queue: Philip Rogers <pdr@chromium.org>
Reviewed-by: Chris Harrelson <chrishtr@chromium.org>
Cr-Commit-Position: refs/heads/master@{#642175}
9 files changed