commit 74e3ab9c9952b51a73bc26c9ea5f3e19eefbd89a
author Justin Miron <justinmiron@google.com> Thu Dec 26 16:31:51 2019
committer Commit Bot <commit-bot@chromium.org> Thu Dec 26 16:31:51 2019
tree 7cbcb073812a8f2376a53ad7f6fe78e503f83d33
parent a08134d8b5bac3412c4038f2c55473f020b357fb

Calculate main frame document intersections for frames.

This change calculates main frame document intersections by adding
new intersection observer state for parent main frame intersections,
propagated down the frame tree in ViewportIntersectionState. It adds
new behavior to bypass clipping to the main frame's viewport when
calculating a frame's intersection with the main frame, enabled by a
new visual rect flag kDontApplyMainFrameOverflowClip.

This is a precursor to two changes:
1. Propagating main frame intersections from render frame observers
through page load metrics to the browser process.
2. Measurement of ad density within the main frame with each ad frames
main frame intersection.

BUG=993453

Change-Id: I7cdc790c6c2ee1047abb397fa3dc55a4c72b8c97
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1968388
Reviewed-by: Ken Buchanan <kenrb@chromium.org>
Reviewed-by: Philip Rogers <pdr@chromium.org>
Reviewed-by: Stefan Zager <szager@chromium.org>
Commit-Queue: Justin Miron <justinmiron@google.com>
Cr-Commit-Position: refs/heads/master@{#727464}