even if there are no idle notifications.

BUG=chromium:515873
LOG=NO

Review URL: https://codereview.chromium.org/1274633003

Cr-Commit-Position: refs/heads/master@{#30062}

Otherwise, if there is no GC and no idle notification,
memory reducer will use old allocation rate.

BUG=chromium:515873
LOG=NO

Review URL: https://codereview.chromium.org/1280623002

Cr-Commit-Position: refs/heads/master@{#30059}

BUG=chromium:515873
LOG=NO

Review URL: https://codereview.chromium.org/1263373002

Cr-Commit-Position: refs/heads/master@{#29996}

BUG=

Review URL: https://codereview.chromium.org/1261373006

Cr-Commit-Position: refs/heads/master@{#29987}

BUG=

Review URL: https://codereview.chromium.org/1262363002

Cr-Commit-Position: refs/heads/master@{#29950}

R=jochen@chromium.org
BUG=511204
LOG=y

Review URL: https://codereview.chromium.org/1246603002

Cr-Commit-Position: refs/heads/master@{#29759}

This is follow-up for a5616e.

BUG=chromium:508584
LOG=NO

Review URL: https://codereview.chromium.org/1234513003

Cr-Commit-Position: refs/heads/master@{#29594}

BUG=chromium:508584
LOG=NO

Review URL: https://codereview.chromium.org/1230163002

Cr-Commit-Position: refs/heads/master@{#29565}

disregarding the allocation throughput.

BUG=chromium:506132
LOG=NO

Review URL: https://codereview.chromium.org/1213313004

Cr-Commit-Position: refs/heads/master@{#29515}

This reverts commit 26991892.
This reverts commit 435b3c87.

The failing test is fixing in chromium.

BUG=chromium:490559
LOG=NO
TBR=hpayer@chromium.org

Review URL: https://codereview.chromium.org/1208993009

Cr-Commit-Position: refs/heads/master@{#29512}

Revert of Replace reduce-memory mode in idle notification with delayed clean-up GC. (patchset #17 id:320001 of https://codereview.chromium.org/1218863002/)

Reason for revert:
[Sheriff] Looks like it blocks the roll (bisected). Speculative revert.
https://codereview.chromium.org/1210293003/

Original issue's description:
> Replace reduce-memory mode in idle notification with delayed clean-up GC.
>
> BUG=490559
> LOG=NO
>
> Committed: https://crrev.com/0ecd9e1bd2c6b519d4e7285f46cb7e844bc2235c
> Cr-Commit-Position: refs/heads/master@{#29451}

TBR=hpayer@chromium.org,ulan@chromium.org
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=490559

Review URL: https://codereview.chromium.org/1226703002

Cr-Commit-Position: refs/heads/master@{#29470}

BUG=490559
LOG=NO

Review URL: https://codereview.chromium.org/1218863002

Cr-Commit-Position: refs/heads/master@{#29451}