The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/eb19371760eee8c9391745b8b955816389f59aee

commit eb19371760eee8c9391745b8b955816389f59aee
Author: Jon Mann <jonmann@chromium.org>
Date: Tue Oct 23 21:54:23 2018

[Android Messages] Add ability to resume streaming session.

This ensures connection to the Android Messages backend is not taken if
another device is active and the user closes the tab or PWA. When the
service worker connects with the backend it needs to send a
START_STREAMING message if the device wasn't previously connected in
order to start receiving messages.  If this message is sent when a
different device is conencted, the other device will lose the
connection. Closing the active tab or PWA is not an action which should
take the connection from another device so in this case we don't want
to send the start message.  This new 'resume_streaming_connection'
informs the service worker that it should connect and not send the
START_STREAMING message.

Bug:  896383 
Change-Id: Ie0e27461d29679c7c969bfd45c39e1dfb39da515
Reviewed-on: https://chromium-review.googlesource.com/c/1287264
Reviewed-by: Kyle Horimoto <khorimoto@chromium.org>
Commit-Queue: Jon Mann <jonmann@chromium.org>
Cr-Commit-Position: refs/heads/master@{#602118}
[modify] https://crrev.com/eb19371760eee8c9391745b8b955816389f59aee/chrome/browser/chromeos/android_sms/connection_establisher.h
[modify] https://crrev.com/eb19371760eee8c9391745b8b955816389f59aee/chrome/browser/chromeos/android_sms/connection_establisher_impl.cc
[modify] https://crrev.com/eb19371760eee8c9391745b8b955816389f59aee/chrome/browser/chromeos/android_sms/connection_establisher_impl.h
[modify] https://crrev.com/eb19371760eee8c9391745b8b955816389f59aee/chrome/browser/chromeos/android_sms/connection_establisher_impl_unittest.cc
[modify] https://crrev.com/eb19371760eee8c9391745b8b955816389f59aee/chrome/browser/chromeos/android_sms/connection_manager.cc
[modify] https://crrev.com/eb19371760eee8c9391745b8b955816389f59aee/chrome/browser/chromeos/android_sms/fake_connection_establisher.cc
[modify] https://crrev.com/eb19371760eee8c9391745b8b955816389f59aee/chrome/browser/chromeos/android_sms/fake_connection_establisher.h