Fix paint invalidation and painting for composited-scrolling input elements.

Fix paint invalidation and painting for composited-scrolling input elements.

In, particular, the following issues:

1. Paint invalidation missed cases when elements had "intrinsic scrollability",
in particular input elements.
2. Invalidation of carets incorrectly included scrolling for composited input
elements.
3. The DisplayItemClient must be distinct for case #2, because it paints into
a different GraphicsLayer than the rest of the LayoutBlock.

BUG=635724
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Committed: https://crrev.com/b1d694f3370e4b6d6e723382c086617f85c94e93
Cr-Commit-Position: refs/heads/master@{#415013}

[chrishtr, 2016-08-23 23:03:32]

Description was changed from

==========
none

BUG=
==========

to

==========
none

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

[chrishtr, 2016-08-23 23:09:17]

Description was changed from

==========
none

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

to

==========
Don't return false for usesCompositedScrolling for "intrinsic scrollability".

This code was added in https://chromiumcodereview.appspot.com/22488004 to
support proper touch event bubbling. However, the test that went with it still
passes with this change. ScrollCoordinator calls usesCompositedScrolling to
determine the rect for computeShouldHandleScrollGestureOnMainThreadRegion.

Should this code be part of PaintLayerScrollableArea::shouldScrollOnMainThread?

BUG=635724
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[chrishtr, 2016-08-23 23:10:19]

chrishtr@chromium.org changed reviewers:
+ bokan@chromium.org, dtapuska@chromium.org

[chrishtr, 2016-08-23 23:10:20]

WDYT? I'm a bit confused about how this particular condition could be needed to
force
main-thread scrolling, but not be part of
PaintLayerScrollableArea::shouldScrollOnMainThread.

[chrishtr, 2016-08-23 23:10:31]

The CQ bit was checked by chrishtr@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-23 23:11:05]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-24 01:25:11]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-24 01:25:12]

Dry run: Try jobs failed on following builders:
  mac_chromium_rel_ng on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/mac_chromium_rel_...)

[chrishtr, 2016-08-24 01:26:57]

FYI I can't commit this as-is due to another problem with carets, but could you
answer my
question about whether this change is ok or somehow breaks things, and if so
how?

[dtapuska, 2016-08-24 13:35:31]

On 2016/08/24 at 01:26:57, chrishtr wrote:
> FYI I can't commit this as-is due to another problem with carets, but could
you answer my
> question about whether this change is ok or somehow breaks things, and if so
how?

I'm deferring to bokan@ :-)

[bokan, 2016-08-24 15:31:05]

On 2016/08/23 23:10:20, chrishtr wrote:
> WDYT? I'm a bit confused about how this particular condition could be needed
to
> force
> main-thread scrolling, but not be part of
> PaintLayerScrollableArea::shouldScrollOnMainThread.

Hey Chris,

It looks to me like PLSA::shouldScrollOnMainThread is used to decide where to
run scroll animations while PLSA::usesCompositedScrolling is used to calculate
the main thread scrolling regions for the compositor. It seems strange that we
have two separate methods for this. I think the reason that condition being only
in the one method hasn't been a problem is because this was meant for touch
scrolling which doesn't use scroll animations. Adding it to
shouldScrollOnMainThread wouldn't hurt though.

I think the reason the test continues to pass is that LayoutTests send events to
the main thread, not CC, so the usesCompositedScrolling decision is moot since
scrolling will happen on the main thread in the test. It's the
userInputScrollable change in my CL that actually made it work once the scroll
happened on the main thread. With this CL, can you touch scroll an input field
with overflowing text? It's possible enough has changed that this isn't actually
needed anymore.

FYI, I think this was the first CL I landed in Chrome so I didn't have a great
understanding of how things worked. There's probably a better way to make the
input box scrollable. IIRC, the reason it didn't work was because
userInputScrollable would check the box's overflow style but the input box
wasn't styled as overflowing; instead, it hid some child elements that were. We
could probably rearrange that make scrolling inputs less special. Maybe it could
even scroll on the compositor, though I'm not sure about how that would work
with selection/carets and the like.

[chrishtr, 2016-08-25 21:13:01]

chrishtr@chromium.org changed reviewers:
+ pdr@chromium.org
- dtapuska@chromium.org

[chrishtr, 2016-08-25 21:13:01]

@bokan: I confirmed that touch scrolling works for an input box (in particular,
the one
referenced as a reduced testcase in the bug attached to this CL). Does the
change to
PaintLayerScrollableArea look ok to you?

@pdr: other than that, the problem was that (a) carets for scrollable inoput
incorrectly included
scroll offset of the input element, and (b) it needs to have its own display
item client,
to preserve separate cacheability from m_graphicsLayer where the rest of the
LayoutBlock
paints. wkorman did the same thing in https://codereview.chromium.org/2254893005

[chrishtr, 2016-08-25 21:13:06]

The CQ bit was checked by chrishtr@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-25 21:14:07]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[chrishtr, 2016-08-25 21:14:53]

Description was changed from

==========
Don't return false for usesCompositedScrolling for "intrinsic scrollability".

This code was added in https://chromiumcodereview.appspot.com/22488004 to
support proper touch event bubbling. However, the test that went with it still
passes with this change. ScrollCoordinator calls usesCompositedScrolling to
determine the rect for computeShouldHandleScrollGestureOnMainThreadRegion.

Should this code be part of PaintLayerScrollableArea::shouldScrollOnMainThread?

BUG=635724
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Fix paint invalidation and painting for composited-scrolling input elements.

In, particular, the following issues:

1. Paint invalidation missed cases when elements had "intrinsic scrollability",
in particular input elements.
2. Invalidation of carets incorrectly included scrolling for composited input
elements.
3. The DisplayItemClient must be distinct for case #2, because it paints into
a different GraphicsLayer than the rest of the LayoutBlock.

BUG=635724
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[commit-bot: I haz the power, 2016-08-25 21:57:58]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-25 21:57:58]

Dry run: Try jobs failed on following builders:
  linux_chromium_chromeos_ozone_rel_ng on master.tryserver.chromium.linux
(JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[pdr., 2016-08-25 22:07:11]

This looks pretty good! The caret-outside-block.html failure looks like a
trivial fix. Just some minor nits / questions.

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Layo...
File third_party/WebKit/LayoutTests/editing/caret/caret-color.html (right):

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Layo...
third_party/WebKit/LayoutTests/editing/caret/caret-color.html:16:
moveSelectionForwardByLineCommand();
nit

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/editing/CaretBase.cpp (right):

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/editing/CaretBase.cpp:148: if
(caretLayoutBlock->usesCompositedScrolling())
usesCompositedScrolling() can change dynamically. Do we need to tell the old
client to invalidate or paint when this occurs?

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/editing/CaretBase.cpp:167: // // FIXME: We should
not allow paint invalidation out of paint invalidation state. crbug.com/457415
Nit: Your comment has a comment

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/BlockPainter.cpp (right):

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/BlockPainter.cpp:197: const
DisplayItemClient& displayItemClient = m_layoutBlock.usesCompositedScrolling() ?
static_cast<const
DisplayItemClient&>(*m_layoutBlock.layer()->graphicsLayerBackingForScrolling())
Nit: are these static cats needed?

[bokan, 2016-08-26 15:38:33]

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp (right):

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp:1480: //
Scroll form controls on the main thread so they exhibit correct touch scroll
event bubbling
This comment is backwards now since we return "don't scroll on main thread" but
I think we could just get rid of this condition altogether.

[chrishtr, 2016-08-26 15:42:36]

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp (right):

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintLayerScrollableArea.cpp:1480: //
Scroll form controls on the main thread so they exhibit correct touch scroll
event bubbling
On 2016/08/26 at 15:38:32, bokan wrote:
> This comment is backwards now since we return "don't scroll on main thread"
but I think we could just get rid of this condition altogether.

Done.

[bokan, 2016-08-26 15:44:23]

PLSA change lgtm

[chrishtr, 2016-08-26 16:02:21]

The CQ bit was checked by chrishtr@chromium.org to run a CQ dry run

[chrishtr, 2016-08-26 16:02:25]

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Layo...
File third_party/WebKit/LayoutTests/editing/caret/caret-color.html (right):

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Layo...
third_party/WebKit/LayoutTests/editing/caret/caret-color.html:16:
moveSelectionForwardByLineCommand();
On 2016/08/25 at 22:07:11, pdr. wrote:
> nit

Done.

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/editing/CaretBase.cpp (right):

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/editing/CaretBase.cpp:167: // // FIXME: We should
not allow paint invalidation out of paint invalidation state. crbug.com/457415
On 2016/08/25 at 22:07:11, pdr. wrote:
> Nit: Your comment has a comment

Done.

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/BlockPainter.cpp (right):

https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/BlockPainter.cpp:197: const
DisplayItemClient& displayItemClient = m_layoutBlock.usesCompositedScrolling() ?
static_cast<const
DisplayItemClient&>(*m_layoutBlock.layer()->graphicsLayerBackingForScrolling())
On 2016/08/25 at 22:07:11, pdr. wrote:
> Nit: are these static cats needed?

In fact, I had forgotten to remove this code now that it's in CaretBase. Done.

[commit-bot: I haz the power, 2016-08-26 16:02:49]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-26 16:06:45]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-26 16:06:46]

Dry run: Try jobs failed on following builders:
  ios-simulator on master.tryserver.chromium.mac (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.mac/builders/ios-simulator/bui...)

[chrishtr, 2016-08-26 16:23:22]

The CQ bit was checked by chrishtr@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-26 16:23:51]

Dry run: CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-26 17:32:37]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-26 17:32:38]

Dry run: Try jobs failed on following builders:
  linux_chromium_asan_rel_ng on master.tryserver.chromium.linux (JOB_FAILED,
http://build.chromium.org/p/tryserver.chromium.linux/builders/linux_chromium_...)

[pdr., 2016-08-26 18:27:13]

On 2016/08/26 at 16:02:25, chrishtr wrote:
>
https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Layo...
> File third_party/WebKit/LayoutTests/editing/caret/caret-color.html (right):
> 
>
https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Layo...
> third_party/WebKit/LayoutTests/editing/caret/caret-color.html:16:
moveSelectionForwardByLineCommand();
> On 2016/08/25 at 22:07:11, pdr. wrote:
> > nit
> 
> Done.
> 
>
https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
> File third_party/WebKit/Source/core/editing/CaretBase.cpp (right):
> 
>
https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
> third_party/WebKit/Source/core/editing/CaretBase.cpp:167: // // FIXME: We
should not allow paint invalidation out of paint invalidation state.
crbug.com/457415
> On 2016/08/25 at 22:07:11, pdr. wrote:
> > Nit: Your comment has a comment
> 
> Done.
> 
>
https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
> File third_party/WebKit/Source/core/paint/BlockPainter.cpp (right):
> 
>
https://codereview.chromium.org/2271883002/diff/60001/third_party/WebKit/Sour...
> third_party/WebKit/Source/core/paint/BlockPainter.cpp:197: const
DisplayItemClient& displayItemClient = m_layoutBlock.usesCompositedScrolling() ?
static_cast<const
DisplayItemClient&>(*m_layoutBlock.layer()->graphicsLayerBackingForScrolling())
> On 2016/08/25 at 22:07:11, pdr. wrote:
> > Nit: are these static cats needed?
> 
> In fact, I had forgotten to remove this code now that it's in CaretBase. Done.

LGTM 2

[chrishtr, 2016-08-26 18:28:00]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2016-08-26 18:28:01]

The patchset sent to the CQ was uploaded after l-g-t-m from bokan@chromium.org,
pdr@chromium.org
Link to the patchset: https://codereview.chromium.org/2271883002/#ps180001
(title: "none")

[commit-bot: I haz the power, 2016-08-26 18:28:34]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-26 20:08:25]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-26 20:08:26]

Try jobs failed on following builders:
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[chrishtr, 2016-08-26 20:11:25]

The CQ bit was checked by chrishtr@chromium.org

[commit-bot: I haz the power, 2016-08-26 20:12:06]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-26 21:57:08]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-26 21:57:10]

Try jobs failed on following builders:
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[chrishtr, 2016-08-26 22:35:54]

The CQ bit was checked by chrishtr@chromium.org

[commit-bot: I haz the power, 2016-08-26 22:36:43]

CQ is trying da patch. Follow status at
 
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[commit-bot: I haz the power, 2016-08-27 01:20:40]

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[commit-bot: I haz the power, 2016-08-27 01:20:41]

Try jobs failed on following builders:
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[chrishtr, 2016-08-27 16:46:24]

The CQ bit was checked by chrishtr@chromium.org

[commit-bot: I haz the power, 2016-08-27 16:46:39]

CQ is trying da patch. Follow status at
 
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[commit-bot: I haz the power, 2016-08-27 18:18:37]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-27 18:18:38]

Try jobs failed on following builders:
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[chrishtr, 2016-08-27 23:44:17]

The CQ bit was checked by chrishtr@chromium.org

[commit-bot: I haz the power, 2016-08-27 23:44:27]

CQ is trying da patch. Follow status at
 
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[commit-bot: I haz the power, 2016-08-28 01:11:27]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-28 01:11:28]

Try jobs failed on following builders:
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[chrishtr, 2016-08-28 02:07:17]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2016-08-28 02:07:17]

The patchset sent to the CQ was uploaded after l-g-t-m from bokan@chromium.org,
pdr@chromium.org
Link to the patchset: https://codereview.chromium.org/2271883002/#ps200001
(title: "none")

[commit-bot: I haz the power, 2016-08-28 02:07:25]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-28 03:21:34]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2016-08-28 03:21:36]

Try jobs failed on following builders:
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[chrishtr, 2016-08-28 21:30:16]

The CQ bit was checked by chrishtr@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-28 21:30:20]

Dry run: CQ is trying da patch. Follow status at
 
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[commit-bot: I haz the power, 2016-08-28 22:51:37]

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[commit-bot: I haz the power, 2016-08-28 22:51:38]

Dry run: Try jobs failed on following builders:
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[chrishtr, 2016-08-29 03:32:31]

The CQ bit was checked by chrishtr@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-29 03:32:48]

Dry run: CQ is trying da patch. Follow status at
 
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[chrishtr, 2016-08-29 03:34:59]

The CQ bit was checked by chrishtr@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2016-08-29 03:35:14]

Dry run: CQ is trying da patch. Follow status at
 
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[commit-bot: I haz the power, 2016-08-29 04:54:08]

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[commit-bot: I haz the power, 2016-08-29 04:54:10]

Dry run: Try jobs failed on following builders:
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[chrishtr, 2016-08-29 04:59:26]

The CQ bit was checked by chrishtr@chromium.org

[chrishtr, 2016-08-29 04:59:26]

The patchset sent to the CQ was uploaded after l-g-t-m from bokan@chromium.org,
pdr@chromium.org
Link to the patchset: https://codereview.chromium.org/2271883002/#ps280001
(title: "none")

[commit-bot: I haz the power, 2016-08-29 04:59:47]

CQ is trying da patch. Follow status at
 
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[commit-bot: I haz the power, 2016-08-29 05:48:32]

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[commit-bot: I haz the power, 2016-08-29 05:48:33]

Try jobs failed on following builders:
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[chrishtr, 2016-08-29 14:44:10]

The CQ bit was checked by chrishtr@chromium.org

[commit-bot: I haz the power, 2016-08-29 14:44:32]

CQ is trying da patch. Follow status at
 
https://chromium-cq-status.appspot.com/v2/patch-status/codereview.chromium.or...

[commit-bot: I haz the power, 2016-08-29 15:37:46]

Committed patchset #15 (id:280001)

[commit-bot: I haz the power, 2016-08-29 15:42:25]

Description was changed from

==========
Fix paint invalidation and painting for composited-scrolling input elements.

In, particular, the following issues:

1. Paint invalidation missed cases when elements had "intrinsic scrollability",
in particular input elements.
2. Invalidation of carets incorrectly included scrolling for composited input
elements.
3. The DisplayItemClient must be distinct for case #2, because it paints into
a different GraphicsLayer than the rest of the LayoutBlock.

BUG=635724
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Fix paint invalidation and painting for composited-scrolling input elements.

In, particular, the following issues:

1. Paint invalidation missed cases when elements had "intrinsic scrollability",
in particular input elements.
2. Invalidation of carets incorrectly included scrolling for composited input
elements.
3. The DisplayItemClient must be distinct for case #2, because it paints into
a different GraphicsLayer than the rest of the LayoutBlock.

BUG=635724
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Committed: https://crrev.com/b1d694f3370e4b6d6e723382c086617f85c94e93
Cr-Commit-Position: refs/heads/master@{#415013}
==========

[commit-bot: I haz the power, 2016-08-29 15:42:26]

Patchset 15 (id:??) landed as
https://crrev.com/b1d694f3370e4b6d6e723382c086617f85c94e93
Cr-Commit-Position: refs/heads/master@{#415013}

[flackr, 2016-08-29 17:00:19]

A revert of this CL (patchset #15 id:280001) has been created in
https://codereview.chromium.org/2286203004/ by flackr@chromium.org.

The reason for reverting is: Broke DisplayItemTest.DebugStringsExist on debug
probably due to adding a new display item type without updating
DisplayItem::typeAsDebugString.

https://uberchromegw.corp.google.com/i/chromium.webkit/builders/WebKit%20Mac1....