So just looked at this.  You can't swipe pending away, it's considered effectively 'in progress' until you pause it.  I think we should leave that behavior as is.  Will fix pause though.

SGTM

Min worked on this earlier today.

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/18aa71703fa522fbd6445fe0e3113e9b98d3c3a4

commit 18aa71703fa522fbd6445fe0e3113e9b98d3c3a4
Author: qinmin <qinmin@chromium.org>
Date: Mon Mar 06 20:38:57 2017

Don't cancel download when dismissing the notification

BUG= 698321 

Review-Url: https://codereview.chromium.org/2729623007
Cr-Commit-Position: refs/heads/master@{#454946}

[modify] https://crrev.com/18aa71703fa522fbd6445fe0e3113e9b98d3c3a4/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadManagerService.java
[modify] https://crrev.com/18aa71703fa522fbd6445fe0e3113e9b98d3c3a4/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadNotificationService.java
[modify] https://crrev.com/18aa71703fa522fbd6445fe0e3113e9b98d3c3a4/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadServiceDelegate.java
[modify] https://crrev.com/18aa71703fa522fbd6445fe0e3113e9b98d3c3a4/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/downloads/OfflinePageDownloadBridge.java
[modify] https://crrev.com/18aa71703fa522fbd6445fe0e3113e9b98d3c3a4/chrome/browser/android/download/download_manager_service.cc
[modify] https://crrev.com/18aa71703fa522fbd6445fe0e3113e9b98d3c3a4/chrome/browser/android/download/download_manager_service.h

Your change meets the bar and is auto-approved for M58. Please go ahead and merge the CL to branch 3029 manually. Please contact milestone owner if you have questions.
Owners: amineer@(clank), cmasso@(bling), bhthompson@(cros), govind@(desktop)

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

The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/67aa8a736b47186e3ea5a2be8cc38bb7583665bd

commit 67aa8a736b47186e3ea5a2be8cc38bb7583665bd
Author: Min Qin <qinmin@chromium.org>
Date: Wed Mar 08 17:24:10 2017

Don't cancel download when dismissing the notification

TBR=dtrainor@chromium.org
BUG= 698321 

Review-Url: https://codereview.chromium.org/2729623007
Cr-Commit-Position: refs/heads/master@{#454946}
(cherry picked from commit 18aa71703fa522fbd6445fe0e3113e9b98d3c3a4)

Review-Url: https://codereview.chromium.org/2737833002 .
Cr-Commit-Position: refs/branch-heads/3029@{#64}
Cr-Branched-From: 939b32ee5ba05c396eef3fd992822fcca9a2e262-refs/heads/master@{#454471}

[modify] https://crrev.com/67aa8a736b47186e3ea5a2be8cc38bb7583665bd/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadManagerService.java
[modify] https://crrev.com/67aa8a736b47186e3ea5a2be8cc38bb7583665bd/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadNotificationService.java
[modify] https://crrev.com/67aa8a736b47186e3ea5a2be8cc38bb7583665bd/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadServiceDelegate.java
[modify] https://crrev.com/67aa8a736b47186e3ea5a2be8cc38bb7583665bd/chrome/android/java/src/org/chromium/chrome/browser/offlinepages/downloads/OfflinePageDownloadBridge.java
[modify] https://crrev.com/67aa8a736b47186e3ea5a2be8cc38bb7583665bd/chrome/browser/android/download/download_manager_service.cc
[modify] https://crrev.com/67aa8a736b47186e3ea5a2be8cc38bb7583665bd/chrome/browser/android/download/download_manager_service.h