Give OOPIF FrameViews their own scroll animation timelines and hosts

Give OOPIF FrameViews their own scroll animation timelines and hosts

OOPIFs need independent scroll animation timelines and hosts, because
they have separate compositors. Ultimately we need to associate a
ScrollingCoordinator which each local frame root, but until that work
is done this CL resolves some known scrolling problems in
--site-per-process mode.

BUG=675695
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2631853002
Cr-Commit-Position: refs/heads/master@{#444947}
(cherry picked from commit 65c7df6e695eb4435ccf5485498b34fd1629f898)

Review-Url: https://codereview.chromium.org/2654883002 .
Cr-Commit-Position: refs/branch-heads/2987@{#62}
Cr-Branched-From: ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed: https://chromium.googlesource.com/chromium/src/+/66ec94ea64f65f9d305390b7636bb49ad00b508c

[kenrb, 2017-01-24 18:27:33]

Description was changed from

==========
Give OOPIF FrameViews their own scroll animation timelines and hosts

OOPIFs need independent scroll animation timelines and hosts, because
they have separate compositors. Ultimately we need to associate a
ScrollingCoordinator which each local frame root, but until that work
is done this CL resolves some known scrolling problems in
--site-per-process mode.

BUG=675695
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2631853002
Cr-Commit-Position: refs/heads/master@{#444947}
(cherry picked from commit 65c7df6e695eb4435ccf5485498b34fd1629f898)
==========

to

==========
Give OOPIF FrameViews their own scroll animation timelines and hosts

OOPIFs need independent scroll animation timelines and hosts, because
they have separate compositors. Ultimately we need to associate a
ScrollingCoordinator which each local frame root, but until that work
is done this CL resolves some known scrolling problems in
--site-per-process mode.

BUG=675695
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Review-Url: https://codereview.chromium.org/2631853002
Cr-Commit-Position: refs/heads/master@{#444947}
(cherry picked from commit 65c7df6e695eb4435ccf5485498b34fd1629f898)

Review-Url: https://codereview.chromium.org/2654883002 .
Cr-Commit-Position: refs/branch-heads/2987@{#62}
Cr-Branched-From:
ad51088c0e8776e8dcd963dbe752c4035ba6dab6-refs/heads/master@{#444943}
Committed:
https://chromium.googlesource.com/chromium/src/+/66ec94ea64f65f9d305390b7636b...
==========

[kenrb, 2017-01-24 18:27:35]

Committed patchset #1 (id:1) manually as
66ec94ea64f65f9d305390b7636bb49ad00b508c.