Does that mean that only that particular icon should have a different color than other icons?

yup..only this icon has a different color..remaining icons should be GG700

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/aef833510f1c295773f2a456db59e72d210c99fd

commit aef833510f1c295773f2a456db59e72d210c99fd
Author: Esmael El-Moslimany <aee@chromium.org>
Date: Tue Jul 10 19:04:52 2018

WebUI: update external link icon color

Bug:  860077 
Cq-Include-Trybots: luci.chromium.try:closure_compilation
Change-Id: I57f482459eaa3f77603dc74025c543ce6a8e5c4f
Reviewed-on: https://chromium-review.googlesource.com/1128204
Reviewed-by: Demetrios Papadopoulos <dpapad@chromium.org>
Commit-Queue: Esmael El-Moslimany <aee@chromium.org>
Cr-Commit-Position: refs/heads/master@{#573843}
[modify] https://crrev.com/aef833510f1c295773f2a456db59e72d210c99fd/chrome/browser/resources/md_history/side_bar.html
[modify] https://crrev.com/aef833510f1c295773f2a456db59e72d210c99fd/ui/webui/resources/images/open_in_new.svg

Able to reproduce the issue on chrome version 69.0.3482.0 (build without fix)
Verified the fix on Windows 10, Mac OS10.13.5, Ubuntu 17.10 using Chrome version # 69.0.3488.0 as per the comment #0.
Attaching screencast for reference.
Observed that  "As we are observed Updated the icon color" 
The fix is working as expected, adding Verified labels

Thanks..!

Deleted: 860077.mp4 481 KB

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