[scheduler] Move DatabaseAccess tasks to loading tq.

[scheduler] Move DatabaseAccess tasks to loading tq.

Posting DatabaseAccess tasks to unthrottled task queue can lead to running websql callbacks when the page is suspended, and it will cause callback to cancel itself.

Post DatabaseAccess tasks to loading queue, which can be suspended and make sure that these tasks run only when page isn't suspended.

R=haraken@chromium.org
CC=skyostil@chromium.org

BUG=700792
Review-Url: https://codereview.chromium.org/2752003002
Cr-Commit-Position: refs/heads/master@{#457145}
(cherry picked from commit 27e68ff784ac0798b46bc596434dd50fbd673887)

Review-Url: https://codereview.chromium.org/2745413005 .
Cr-Commit-Position: refs/branch-heads/2987@{#826}
Cr-Branched-From: ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed: https://chromium.googlesource.com/chromium/src/+/faad12b9a164462d05626473b8caac31281d4fb6

[Sami, 2017-03-15 18:46:43]

Description was changed from

==========
[scheduler] Move DatabaseAccess tasks to loading tq.

Posting DatabaseAccess tasks to unthrottled task queue can lead to running
websql callbacks when the page is suspended, and it will cause callback to
cancel itself.

Post DatabaseAccess tasks to loading queue, which can be suspended and make sure
that these tasks run only when page isn't suspended.

R=haraken@chromium.org
CC=skyostil@chromium.org

BUG=700792

Review-Url: https://codereview.chromium.org/2752003002
Cr-Commit-Position: refs/heads/master@{#457145}
(cherry picked from commit 27e68ff784ac0798b46bc596434dd50fbd673887)
==========

to

==========
[scheduler] Move DatabaseAccess tasks to loading tq.

Posting DatabaseAccess tasks to unthrottled task queue can lead to running
websql callbacks when the page is suspended, and it will cause callback to
cancel itself.

Post DatabaseAccess tasks to loading queue, which can be suspended and make sure
that these tasks run only when page isn't suspended.

R=haraken@chromium.org
CC=skyostil@chromium.org

BUG=700792

Review-Url: https://codereview.chromium.org/2752003002
Cr-Commit-Position: refs/heads/master@{#457145}
(cherry picked from commit 27e68ff784ac0798b46bc596434dd50fbd673887)

Review-Url: https://codereview.chromium.org/2745413005 .
Cr-Commit-Position: refs/branch-heads/2987@{#826}
Cr-Branched-From:
ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed:
https://chromium.googlesource.com/chromium/src/+/faad12b9a164462d05626473b8ca...
==========

[Sami, 2017-03-15 18:46:45]

Committed patchset #1 (id:1) manually as
faad12b9a164462d05626473b8caac31281d4fb6.