The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/95ecf6b551fe3a33c23f2882188b9aa68ee5d930

commit 95ecf6b551fe3a33c23f2882188b9aa68ee5d930
Author: Peter E Conn <peconn@chromium.org>
Date: Mon Jul 09 13:27:52 2018

🤝 Use new Intent flags while creating the TWA Intent.

The ChromeLauncherActivity has android:excludeFromRecents="true" set in
the AndroidManifest.xml. This causes the Intent used to launch it to
have Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS set. The Intent used to
launch a Trusted Web Activity copies the flag from this first Intent.

As I can currently see not advantage to copying the flags over, this
CL stops this and therefore prevents TWAs being launched with
Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS.

Bug:  860325 
Change-Id: I135bd9f5a070e5b34a0fedaf6d66714604712170
Reviewed-on: https://chromium-review.googlesource.com/1126390
Commit-Queue: Peter Conn <peconn@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Reviewed-by: Benoit L <lizeb@chromium.org>
Reviewed-by: Yaron Friedman <yfriedman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#573286}
[modify] https://crrev.com/95ecf6b551fe3a33c23f2882188b9aa68ee5d930/chrome/android/java/src/org/chromium/chrome/browser/LaunchIntentDispatcher.java