Not sure why bugdroid didn't update this bug. But the CL merged and is here: https://chromium-review.googlesource.com/c/chromium/src/+/1200463

Your change meets the bar and is auto-approved for M70. Please go ahead and merge the CL to branch 3538 manually. Please contact milestone owner if you have questions.
Owners: benmason@(Android), kariahda@(iOS), geohsu@(ChromeOS), abdulsyed@(Desktop)

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

Verified in 71.0.3543.0 build, now it is reading button name only one time 

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/62ebf0a512c16992819b555014cdd9ce6ade383e

commit 62ebf0a512c16992819b555014cdd9ce6ade383e
Author: Pedro Amaral <amaralp@chromium.org>
Date: Tue Sep 04 19:54:21 2018

Removing "button" from search accelerator accessibility string

Bug:  879742 
Change-Id: Ibb6746cdff1a7050112b83a1b451a55ba16522ae
Reviewed-on: https://chromium-review.googlesource.com/1200463
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Pedro Amaral <amaralp@chromium.org>
Cr-Commit-Position: refs/heads/master@{#588625}
[modify] https://crrev.com/62ebf0a512c16992819b555014cdd9ce6ade383e/chrome/android/java/strings/android_chrome_strings.grd

This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

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This issue has been approved for a merge. Please merge the fix to any appropriate branches as soon as possible!

If all merges have been completed, please remove any remaining Merge-Approved labels from this issue.

Thanks for your time! To disable nags, add the Disable-Nags label.

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The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/b00b95855934d53226bd2efb365b85489a0e8c3c

commit b00b95855934d53226bd2efb365b85489a0e8c3c
Author: Pedro Amaral <amaralp@chromium.org>
Date: Fri Sep 14 18:06:36 2018

Removing "button" from search accelerator accessibility string

TBR=amaralp@chromium.org

(cherry picked from commit 62ebf0a512c16992819b555014cdd9ce6ade383e)

Bug:  879742 
Change-Id: Ibb6746cdff1a7050112b83a1b451a55ba16522ae
Reviewed-on: https://chromium-review.googlesource.com/1200463
Reviewed-by: Matthew Jones <mdjones@chromium.org>
Commit-Queue: Pedro Amaral <amaralp@chromium.org>
Cr-Original-Commit-Position: refs/heads/master@{#588625}
Reviewed-on: https://chromium-review.googlesource.com/1227170
Reviewed-by: Pedro Amaral <amaralp@chromium.org>
Cr-Commit-Position: refs/branch-heads/3538@{#407}
Cr-Branched-From: 79f7c91a2b2a2932cd447fa6f865cb6662fa8fa6-refs/heads/master@{#587811}
[modify] https://crrev.com/b00b95855934d53226bd2efb365b85489a0e8c3c/chrome/android/java/strings/android_chrome_strings.grd