Icon next to "Show Full History" should be the original clock icon that was on the NTP. 
Justin: Do you have the needed asset? If not, please ask Amy or Pete. 

clock icon is available here if needed https://icons.googleplex.com/#icon=ic_schedule&search=clock

CL is waiting review here: https://codereview.chromium.org/2638953002/

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/6c6dcbedc1786d4545442f588733ed6e3b171a38

commit 6c6dcbedc1786d4545442f588733ed6e3b171a38
Author: justincohen <justincohen@chromium.org>
Date: Wed Jan 18 15:48:40 2017

[ios] Put back clock open for recently closed image.

BUG= 681635 

Review-Url: https://codereview.chromium.org/2638953002
Cr-Commit-Position: refs/heads/master@{#444372}

[modify] https://crrev.com/6c6dcbedc1786d4545442f588733ed6e3b171a38/ios/chrome/browser/ui/ntp/BUILD.gn
[modify] https://crrev.com/6c6dcbedc1786d4545442f588733ed6e3b171a38/ios/chrome/browser/ui/ntp/recent_tabs/views/show_full_history_view.mm
[add] https://crrev.com/6c6dcbedc1786d4545442f588733ed6e3b171a38/ios/chrome/browser/ui/ntp/resources/ntp_opentabs_clock.png
[add] https://crrev.com/6c6dcbedc1786d4545442f588733ed6e3b171a38/ios/chrome/browser/ui/ntp/resources/ntp_opentabs_clock@2x.png
[add] https://crrev.com/6c6dcbedc1786d4545442f588733ed6e3b171a38/ios/chrome/browser/ui/ntp/resources/ntp_opentabs_clock@3x.png

Verified the issue on the build 57.0.2987.88 dev tested on iPhone7+(iOS 10),iPhone5s(9.3.5).
Clock icon is displayed next to show full history in recent tabs,looks good.