scheduler: Make DOM window event tasks unthrottled

scheduler: Make DOM window event tasks unthrottled

This patch avoids throttling events that are routed via
DOMWindowEventQueue. This affects a handful of window-related events,
the most important ones being IndexedDB events. It turns out many web
pages (e.g., Google Docs) rely on IndexedDB transactions to be
relatively fast and start encountering errors if they are throttled too
aggressively while a tab is in the background.

BUG=675372
Review-Url: https://codereview.chromium.org/2651933002
Cr-Commit-Position: refs/heads/master@{#446000}
(cherry picked from commit 05a13309259dd16f38eef41adc7cce55e3d15a05)

Review-Url: https://codereview.chromium.org/2658583006 .
Cr-Commit-Position: refs/branch-heads/2987@{#111}
Cr-Branched-From: ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed: https://chromium.googlesource.com/chromium/src/+/e695fd410c82bc1909531ec7cbbfc03f9d6a5d0e

[Sami, 2017-01-26 18:40:23]

Description was changed from

==========
scheduler: Make DOM window event tasks unthrottled

This patch avoids throttling events that are routed via
DOMWindowEventQueue. This affects a handful of window-related events,
the most important ones being IndexedDB events. It turns out many web
pages (e.g., Google Docs) rely on IndexedDB transactions to be
relatively fast and start encountering errors if they are throttled too
aggressively while a tab is in the background.

BUG=675372

Review-Url: https://codereview.chromium.org/2651933002
Cr-Commit-Position: refs/heads/master@{#446000}
(cherry picked from commit 05a13309259dd16f38eef41adc7cce55e3d15a05)
==========

to

==========
scheduler: Make DOM window event tasks unthrottled

This patch avoids throttling events that are routed via
DOMWindowEventQueue. This affects a handful of window-related events,
the most important ones being IndexedDB events. It turns out many web
pages (e.g., Google Docs) rely on IndexedDB transactions to be
relatively fast and start encountering errors if they are throttled too
aggressively while a tab is in the background.

BUG=675372

Review-Url: https://codereview.chromium.org/2651933002
Cr-Commit-Position: refs/heads/master@{#446000}
(cherry picked from commit 05a13309259dd16f38eef41adc7cce55e3d15a05)

Review-Url: https://codereview.chromium.org/2658583006 .
Cr-Commit-Position: refs/branch-heads/2987@{#111}
Cr-Branched-From:
ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed:
https://chromium.googlesource.com/chromium/src/+/e695fd410c82bc1909531ec7cbbf...
==========

[Sami, 2017-01-26 18:40:26]

Committed patchset #1 (id:1) manually as
e695fd410c82bc1909531ec7cbbfc03f9d6a5d0e (tree was closed).