The following revision refers to this bug:
  https://chromium.googlesource.com/chromium/src.git/+/fe416305b68801e7728dd8482fa309b62698199a

commit fe416305b68801e7728dd8482fa309b62698199a
Author: Joy Ming <jming@chromium.org>
Date: Wed Aug 09 16:51:48 2017

Create DownloadBroadcastManager to handle communication to native.

This is part of a larger refactor to make downloads a foreground
service. This handles the propagation of notification interaction
to native. Before, the path was DownloadBroadcastReceiver->
DownloadNotificationService->native. This CL takes the logic
relating to spinning up and communicating to the native out of the
DownloadNotificationService and into DownloadBroadcastManager, making
the path DBR->DNS->DBM->native. The reason this still routes through
the DownloadNotificationService is because currently DNS still handles
some non-native logic (ie. updating the notifications). After the
refactor is completed, the notification interaction will no longer
have to be routed through the DownloadNotificationService and the
path will be DBR->DBM->native, where the DownloadBroadcastManager
will be a service that just spins up and communicates to native.

Bug:  747569 , 747563 
Change-Id: I27ff959b31cebba8f44fc2cc1cebfbeaf466cb64
Reviewed-on: https://chromium-review.googlesource.com/581870
Commit-Queue: Joy Ming <jming@chromium.org>
Reviewed-by: David Trainor <dtrainor@chromium.org>
Cr-Commit-Position: refs/heads/master@{#493025}
[add] https://crrev.com/fe416305b68801e7728dd8482fa309b62698199a/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadBroadcastManager.java
[modify] https://crrev.com/fe416305b68801e7728dd8482fa309b62698199a/chrome/android/java/src/org/chromium/chrome/browser/download/DownloadNotificationService.java
[modify] https://crrev.com/fe416305b68801e7728dd8482fa309b62698199a/chrome/android/java_sources.gni
[modify] https://crrev.com/fe416305b68801e7728dd8482fa309b62698199a/chrome/android/javatests/src/org/chromium/chrome/browser/download/DownloadNotificationServiceTest.java
[modify] https://crrev.com/fe416305b68801e7728dd8482fa309b62698199a/chrome/android/javatests/src/org/chromium/chrome/browser/download/MockDownloadNotificationService.java