The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6f49be301a8bb3494401f9cc725b0430fafb5c29

commit 6f49be301a8bb3494401f9cc725b0430fafb5c29
Author: Ryan Landay <rlanday@chromium.org>
Date: Fri Jun 08 16:48:16 2018

Fix clipping bug using Android horizontal tab switcher in RTL mode

The Android horizontal tab switcher is currently using the same
clipping/visibility logic as the existing overlapping tab switcher. This logic
is largely unnecessary and is in fact causing a bug in RTL mode when we try to
clip a tab from the left side as it goes off-screen (ContentLayer doesn't
properly support clipping the live layer in this case).

This CL splits up the visibility/clipping logic for the overlapping and
non-overlapping tab switchers. For the non-overlapping tab switcher, the only
logic we need is a performance optimization to only draw at most four tabs,
based on which tab is currently centered.

Bug:  849930 ,831359
Change-Id: Ia000e91b91615acf9f6b071b2d501ee55da231cc
Reviewed-on: https://chromium-review.googlesource.com/1091164
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Ryan Landay <rlanday@chromium.org>
Cr-Commit-Position: refs/heads/master@{#565658}
[modify] https://crrev.com/6f49be301a8bb3494401f9cc725b0430fafb5c29/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/phone/stack/NonOverlappingStack.java
[modify] https://crrev.com/6f49be301a8bb3494401f9cc725b0430fafb5c29/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/phone/stack/OverlappingStack.java
[modify] https://crrev.com/6f49be301a8bb3494401f9cc725b0430fafb5c29/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/phone/stack/Stack.java

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6cb785f849a339be621344233749bdcbe68f8e99

commit 6cb785f849a339be621344233749bdcbe68f8e99
Author: Ryan Landay <rlanday@chromium.org>
Date: Fri Jun 08 16:59:27 2018

Fix clipping bug using Android horizontal tab switcher in RTL mode

The Android horizontal tab switcher is currently using the same
clipping/visibility logic as the existing overlapping tab switcher. This logic
is largely unnecessary and is in fact causing a bug in RTL mode when we try to
clip a tab from the left side as it goes off-screen (ContentLayer doesn't
properly support clipping the live layer in this case).

This CL splits up the visibility/clipping logic for the overlapping and
non-overlapping tab switchers. For the non-overlapping tab switcher, the only
logic we need is a performance optimization to only draw at most four tabs,
based on which tab is currently centered.

(cherry picked from commit bc1919803000e53e492c9ae1eb30755a06167d98)


TBR=rlanday@chromium.org

Bug:  849930 ,831359
Change-Id: I544bab789c5907480d95e36a56916f8eb0f4b936
Reviewed-on: https://chromium-review.googlesource.com/1092796
Reviewed-by: Ryan Landay <rlanday@chromium.org>
Cr-Commit-Position: refs/branch-heads/3440@{#260}
Cr-Branched-From: 010ddcfda246975d194964ccf20038ebbdec6084-refs/heads/master@{#561733}
[modify] https://crrev.com/6cb785f849a339be621344233749bdcbe68f8e99/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/phone/stack/NonOverlappingStack.java
[modify] https://crrev.com/6cb785f849a339be621344233749bdcbe68f8e99/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/phone/stack/OverlappingStack.java
[modify] https://crrev.com/6cb785f849a339be621344233749bdcbe68f8e99/chrome/android/java/src/org/chromium/chrome/browser/compositor/layouts/phone/stack/Stack.java

was this merge approved somewhere?

The tracking bug for the horizontal tab switcher, 849930, has Merge-Approved-68

Sorry, 831359