Only set the FLAG_RECEIVER_FOREGROUND flag for Web Notifications on >=N

We understand what this behaviour does in cases where the Job
Scheduler is used to deliver Web Notification events, but aren't
sure of its behaviour on older versions of Android as it influences
the time we're allowed to run for. Limit it to >= Android N in
order to reduce the risk.

R=awdf
BUG=764437

Change-Id: Ib398adb3ac2ff61a93282639956e092d8315fb57
Reviewed-on: https://chromium-review.googlesource.com/755194
Commit-Queue: Peter Beverloo <peter@chromium.org>
Reviewed-by: Anita Woodruff <awdf@chromium.org>
Cr-Commit-Position: refs/heads/master@{#514203}
1 file changed