Assigning to sczs@chromium.org because ramyasharma@ is OOO.

Taking this as I fixed it for Reading List, it would be almost the same fix.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/93431873bb6abd9b9034d107de73e7f440dce74d

commit 93431873bb6abd9b9034d107de73e7f440dce74d
Author: Gauthier Ambard <gambard@chromium.org>
Date: Mon Sep 18 15:34:35 2017

Fix History bottom toolbar on iPhone X

On iPhone X, the safe area is cutting the bottom and sides of the
device. The bottom toolbar needs to take it into account to be
correctly displayed on iPhone X.

Before: https://drive.google.com/file/d/0By4O1f2IQqQ_aE9PcnJoblpocTQ/view
After: https://drive.google.com/open?id=0B21N-0pPGAuJVG9YMkU2ZDdONVE

Bug:  765397 
Change-Id: I20eea4ab32089cb5fb2850166b04c19425ba04de
Reviewed-on: https://chromium-review.googlesource.com/668578
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Cr-Commit-Position: refs/heads/master@{#502582}
[modify] https://crrev.com/93431873bb6abd9b9034d107de73e7f440dce74d/ios/chrome/browser/ui/history/clear_browsing_bar.mm
[modify] https://crrev.com/93431873bb6abd9b9034d107de73e7f440dce74d/ios/chrome/browser/ui/history/history_panel_view_controller.mm

This should only change on iPhone X, the behavior for the other devices should be the same.
Asking for merge on M62.

This bug requires manual review: Less than 25 days to go before AppStore submit on M62
Please contact the milestone owner if you have questions.
Owners: amineer@(Android), cmasso@(iOS), bhthompson@(ChromeOS), abdulsyed@(Desktop)

For more details visit https://www.chromium.org/issue-tracking/autotriage - Your friendly Sheriffbot

ClearBrowsingData and Edit buttons are displayed correctly on iPhoneX (Both Landscape and Portrait)
Screenshots:
CBD and Edit buttons on iPhoneX (Landscape) https://drive.google.com/file/d/0B-xmXLQhjeKudE9NV3A4TlBjNms/view
CBD and Edit buttons on iPhoneX https://drive.google.com/file/d/0B-xmXLQhjeKub1J3Ty1ndHAyQ1U/view
Delete and Cancel buttons iPhoneX (Landscape) https://drive.google.com/file/d/0B-xmXLQhjeKuQTdsbXpGcmtfOE0/view
Delete and Cancel buttons iPhoneX https://drive.google.com/file/d/0B-xmXLQhjeKuODN2aHhDbkdpaG8/view

Verified on M63.0.3220.0 Simulator

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/bdc0316fe6e99cc025a3a4dafcd4038fdb20277a

commit bdc0316fe6e99cc025a3a4dafcd4038fdb20277a
Author: Gauthier Ambard <gambard@chromium.org>
Date: Wed Sep 20 07:09:28 2017

Fix History bottom toolbar on iPhone X

On iPhone X, the safe area is cutting the bottom and sides of the
device. The bottom toolbar needs to take it into account to be
correctly displayed on iPhone X.

Before: https://drive.google.com/file/d/0By4O1f2IQqQ_aE9PcnJoblpocTQ/view
After: https://drive.google.com/open?id=0B21N-0pPGAuJVG9YMkU2ZDdONVE

Bug:  765397 
Change-Id: I20eea4ab32089cb5fb2850166b04c19425ba04de
Reviewed-on: https://chromium-review.googlesource.com/668578
Commit-Queue: Gauthier Ambard <gambard@chromium.org>
Reviewed-by: Sergio Collazos <sczs@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#502582}(cherry picked from commit 93431873bb6abd9b9034d107de73e7f440dce74d)
Reviewed-on: https://chromium-review.googlesource.com/674904
Reviewed-by: Gauthier Ambard <gambard@chromium.org>
Cr-Commit-Position: refs/branch-heads/3202@{#351}
Cr-Branched-From: fa6a5d87adff761bc16afc5498c3f5944c1daa68-refs/heads/master@{#499098}
[modify] https://crrev.com/bdc0316fe6e99cc025a3a4dafcd4038fdb20277a/ios/chrome/browser/ui/history/clear_browsing_bar.mm
[modify] https://crrev.com/bdc0316fe6e99cc025a3a4dafcd4038fdb20277a/ios/chrome/browser/ui/history/history_panel_view_controller.mm