Revert of Use NGLogicalRect instead of NGExclusion for exclusions. (patchset #5 id:110016 of https://codereview.chromium.org/2457013004/ )

Reason for revert:
Reverting to enable reverting of https://codereview.chromium.org/2458253002/ in https://codereview.chromium.org/2458253002/ due to  merge conflicts.

Please reland once the flakiness has been sorted out.

Original issue's description:
> Use NGLogicalRect instead of NGExclusion to work with exclusions.
>
> This patch does the following:
> - Delete NGExclusion
> - Change the code to use NGLogicalRect to store exclusions
> - Make NGPhysicalConstraintSpace to own the list of exclusions through Vector<std::unique_ptr>
> - Introduce WRITING_MODE_IGNORED macros that can be used to annotate cases where the writing mode is inored
>
> BUG=635619
>
> Committed: https://crrev.com/250a6979a3311cb8a39ca7d7f316353550362f86
> Cr-Commit-Position: refs/heads/master@{#428907}

TBR=cbiesinger@chromium.org,eae@chromium.org,ikilpatrick@chromium.org,dpranke@chromium.org,glebl@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=635619

Review-Url: https://codereview.chromium.org/2467803002
Cr-Commit-Position: refs/heads/master@{#428971}
14 files changed