[M55] Generalize layer mirroring for phantom windows

[M55] Generalize layer mirroring for phantom windows

Previously, the layers of a phantom window were recreated when the
surface changed in the corresponding layers of the original window.
The code also assumed that layers with surfaces are leaves in the
layer tree, but Exosphere surfaces are nested. Recursive layer
cloning would be inefficient for surfaces changing in each frame,
so this CL adds an alternative way to mirror layers. In addition,
the bounds of Exosphere surfaces relative to their parent window
are updated whenever the window moves, so this CL provides a way
to synchronize relative positions of layers in phantom windows.

In addition to implementing phantom windows for ARC apps, this CL
fixes three bugs related to mirroring:

  1) Memory corruption due to the non-recursive layer cloning.
  2) Dangling pointers due to observers sticking around.
  3) Black Alt+Tab previews for ARC windows.

BUG=642894
BUG=649452
BUG=653113
TEST=ARC apps that render continuously (e.g. games, video players)
     can be dragged to external displays, and their content is
     mirrored in phantom windows.
TEST=ARC apps are mirrored in Alt+Tab previews.

Review-Url: https://codereview.chromium.org/2383263002
Cr-Commit-Position: refs/heads/master@{#427891}
(cherry picked from commit 4b33bfeda856f7ae20ffa43176e5bd529d5a100a)
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
R=oshima@chromium.org, sky@chromium.org

Committed: https://chromium.googlesource.com/chromium/src/+/cc5903023a09b0560e4041daa109c7b5431f7cb4

[Dominik Laskowski, 2016-10-28 20:41:30]

Description was changed from

==========
[M55] Generalize layer mirroring for phantom windows

Previously, the layers of a phantom window were recreated when the
surface changed in the corresponding layers of the original window.
The code also assumed that layers with surfaces are leaves in the
layer tree, but Exosphere surfaces are nested. Recursive layer
cloning would be inefficient for surfaces changing in each frame,
so this CL adds an alternative way to mirror layers. In addition,
the bounds of Exosphere surfaces relative to their parent window
are updated whenever the window moves, so this CL provides a way
to synchronize relative positions of layers in phantom windows.

In addition to implementing phantom windows for ARC apps, this CL
fixes three bugs related to mirroring:

  1) Memory corruption due to the non-recursive layer cloning.
  2) Dangling pointers due to observers sticking around.
  3) Black Alt+Tab previews for ARC windows.

BUG=642894
BUG=649452
BUG=653113
TEST=ARC apps that render continuously (e.g. games, video players)
     can be dragged to external displays, and their content is
     mirrored in phantom windows.
TEST=ARC apps are mirrored in Alt+Tab previews.

Review-Url: https://codereview.chromium.org/2383263002
Cr-Commit-Position: refs/heads/master@{#427891}
(cherry picked from commit 4b33bfeda856f7ae20ffa43176e5bd529d5a100a)
==========

to

==========
[M55] Generalize layer mirroring for phantom windows

Previously, the layers of a phantom window were recreated when the
surface changed in the corresponding layers of the original window.
The code also assumed that layers with surfaces are leaves in the
layer tree, but Exosphere surfaces are nested. Recursive layer
cloning would be inefficient for surfaces changing in each frame,
so this CL adds an alternative way to mirror layers. In addition,
the bounds of Exosphere surfaces relative to their parent window
are updated whenever the window moves, so this CL provides a way
to synchronize relative positions of layers in phantom windows.

In addition to implementing phantom windows for ARC apps, this CL
fixes three bugs related to mirroring:

  1) Memory corruption due to the non-recursive layer cloning.
  2) Dangling pointers due to observers sticking around.
  3) Black Alt+Tab previews for ARC windows.

BUG=642894
BUG=649452
BUG=653113
TEST=ARC apps that render continuously (e.g. games, video players)
     can be dragged to external displays, and their content is
     mirrored in phantom windows.
TEST=ARC apps are mirrored in Alt+Tab previews.

Review-Url: https://codereview.chromium.org/2383263002
Cr-Commit-Position: refs/heads/master@{#427891}
(cherry picked from commit 4b33bfeda856f7ae20ffa43176e5bd529d5a100a)
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
==========

[Dominik Laskowski, 2016-10-28 21:00:59]

domlaskowski@chromium.org changed reviewers:
+ danakj@chromium.org, oshima@chromium.org, reveman@chromium.org,
sadrul@chromium.org, sky@chromium.org

[Dominik Laskowski, 2016-10-28 21:00:59]

PTAL. The only change is the addition of a PrepareForLayerBoundsChange override
in Layer::LayerMirror, which is needed because M55 does not include
crrev.com/6627dfc6e2247fd121673698eef9398c52fcd82d.

[oshima, 2016-10-28 21:26:46]

lgtm

[sky, 2016-10-28 21:35:00]

LGTM - in the future please upload your original patch as the first, and any
changes as a subsequent patch to make diffing easy.

[oshima, 2016-10-28 21:59:09]

Description was changed from

==========
[M55] Generalize layer mirroring for phantom windows

Previously, the layers of a phantom window were recreated when the
surface changed in the corresponding layers of the original window.
The code also assumed that layers with surfaces are leaves in the
layer tree, but Exosphere surfaces are nested. Recursive layer
cloning would be inefficient for surfaces changing in each frame,
so this CL adds an alternative way to mirror layers. In addition,
the bounds of Exosphere surfaces relative to their parent window
are updated whenever the window moves, so this CL provides a way
to synchronize relative positions of layers in phantom windows.

In addition to implementing phantom windows for ARC apps, this CL
fixes three bugs related to mirroring:

  1) Memory corruption due to the non-recursive layer cloning.
  2) Dangling pointers due to observers sticking around.
  3) Black Alt+Tab previews for ARC windows.

BUG=642894
BUG=649452
BUG=653113
TEST=ARC apps that render continuously (e.g. games, video players)
     can be dragged to external displays, and their content is
     mirrored in phantom windows.
TEST=ARC apps are mirrored in Alt+Tab previews.

Review-Url: https://codereview.chromium.org/2383263002
Cr-Commit-Position: refs/heads/master@{#427891}
(cherry picked from commit 4b33bfeda856f7ae20ffa43176e5bd529d5a100a)
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
==========

to

==========
[M55] Generalize layer mirroring for phantom windows

Previously, the layers of a phantom window were recreated when the
surface changed in the corresponding layers of the original window.
The code also assumed that layers with surfaces are leaves in the
layer tree, but Exosphere surfaces are nested. Recursive layer
cloning would be inefficient for surfaces changing in each frame,
so this CL adds an alternative way to mirror layers. In addition,
the bounds of Exosphere surfaces relative to their parent window
are updated whenever the window moves, so this CL provides a way
to synchronize relative positions of layers in phantom windows.

In addition to implementing phantom windows for ARC apps, this CL
fixes three bugs related to mirroring:

  1) Memory corruption due to the non-recursive layer cloning.
  2) Dangling pointers due to observers sticking around.
  3) Black Alt+Tab previews for ARC windows.

BUG=642894
BUG=649452
BUG=653113
TEST=ARC apps that render continuously (e.g. games, video players)
     can be dragged to external displays, and their content is
     mirrored in phantom windows.
TEST=ARC apps are mirrored in Alt+Tab previews.

Review-Url: https://codereview.chromium.org/2383263002
Cr-Commit-Position: refs/heads/master@{#427891}
(cherry picked from commit 4b33bfeda856f7ae20ffa43176e5bd529d5a100a)
CQ_INCLUDE_TRYBOTS=master.tryserver.blink:linux_precise_blink_rel
R=oshima@chromium.org, sky@chromium.org

Committed:
https://chromium.googlesource.com/chromium/src/+/cc5903023a09b0560e4041daa109...
==========

[oshima, 2016-10-28 21:59:10]

Committed patchset #1 (id:1) manually as
cc5903023a09b0560e4041daa109c7b5431f7cb4.