[css-grid] Use firstInFlowChildBox API for iterate over the grid items

[css-grid] Use firstInFlowChildBox API for iterate over the grid items

We are using the nextInFlowSiblingBox API for iterating over the grid
items in an inefficient way, because we are checking for every box
whether it's out-of-flow or not. This operation is redundant, since it's
already done internally in nextInFlowSiblingBox.

The only reason why we implemented it that way is that we needed to
check out the nature of the first child. This patch adds a new API for
getting the first in-flow child box, so we can implement the loops
without the redundant operations.

Committed: https://crrev.com/d0d28056752b04b36f5acce5452d1cd64ce4d5c3
Cr-Commit-Position: refs/heads/master@{#425962}

[jfernandez, 2016-10-18 13:30:20]

Description was changed from

==========
[css-grid] Use firstInFlowChildBox API for iterate over the grid items

We are using the nextInFlowSiblingBox API for iterating over the grid
items in an inefficient way, because we are checking for every box
whether it's out-of-flow or not. This operation is redundant, since it's
already done internally in nextInFlowSiblingBox.

The only reason why we implemented it that way is that we needed to
check out the nature of the first child. This patch adds a new API for
getting the first in-flow child box, so we can implement the loops
without the redundant operations.
==========

to

==========
[css-grid] Use firstInFlowChildBox API for iterate over the grid items

We are using the nextInFlowSiblingBox API for iterating over the grid
items in an inefficient way, because we are checking for every box
whether it's out-of-flow or not. This operation is redundant, since it's
already done internally in nextInFlowSiblingBox.

The only reason why we implemented it that way is that we needed to
check out the nature of the first child. This patch adds a new API for
getting the first in-flow child box, so we can implement the loops
without the redundant operations.
==========

[jfernandez, 2016-10-18 13:30:20]

jfernandez@igalia.com changed reviewers:
+ cbiesinger@chromium.org, rego@igalia.com, svillar@igalia.com

[cbiesinger, 2016-10-18 13:32:33]

lgtm

[jfernandez, 2016-10-18 13:39:15]

The CQ bit was checked by jfernandez@igalia.com

[commit-bot: I haz the power, 2016-10-18 13:39:45]

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, 2016-10-18 14:53:25]

Description was changed from

==========
[css-grid] Use firstInFlowChildBox API for iterate over the grid items

We are using the nextInFlowSiblingBox API for iterating over the grid
items in an inefficient way, because we are checking for every box
whether it's out-of-flow or not. This operation is redundant, since it's
already done internally in nextInFlowSiblingBox.

The only reason why we implemented it that way is that we needed to
check out the nature of the first child. This patch adds a new API for
getting the first in-flow child box, so we can implement the loops
without the redundant operations.
==========

to

==========
[css-grid] Use firstInFlowChildBox API for iterate over the grid items

We are using the nextInFlowSiblingBox API for iterating over the grid
items in an inefficient way, because we are checking for every box
whether it's out-of-flow or not. This operation is redundant, since it's
already done internally in nextInFlowSiblingBox.

The only reason why we implemented it that way is that we needed to
check out the nature of the first child. This patch adds a new API for
getting the first in-flow child box, so we can implement the loops
without the redundant operations.
==========

[commit-bot: I haz the power, 2016-10-18 14:53:26]

Committed patchset #1 (id:1)

[commit-bot: I haz the power, 2016-10-18 14:56:35]

Description was changed from

==========
[css-grid] Use firstInFlowChildBox API for iterate over the grid items

We are using the nextInFlowSiblingBox API for iterating over the grid
items in an inefficient way, because we are checking for every box
whether it's out-of-flow or not. This operation is redundant, since it's
already done internally in nextInFlowSiblingBox.

The only reason why we implemented it that way is that we needed to
check out the nature of the first child. This patch adds a new API for
getting the first in-flow child box, so we can implement the loops
without the redundant operations.
==========

to

==========
[css-grid] Use firstInFlowChildBox API for iterate over the grid items

We are using the nextInFlowSiblingBox API for iterating over the grid
items in an inefficient way, because we are checking for every box
whether it's out-of-flow or not. This operation is redundant, since it's
already done internally in nextInFlowSiblingBox.

The only reason why we implemented it that way is that we needed to
check out the nature of the first child. This patch adds a new API for
getting the first in-flow child box, so we can implement the loops
without the redundant operations.

Committed: https://crrev.com/d0d28056752b04b36f5acce5452d1cd64ce4d5c3
Cr-Commit-Position: refs/heads/master@{#425962}
==========

[commit-bot: I haz the power, 2016-10-18 14:56:37]

Patchset 1 (id:??) landed as
https://crrev.com/d0d28056752b04b36f5acce5452d1cd64ce4d5c3
Cr-Commit-Position: refs/heads/master@{#425962}

[Manuel Rego, 2016-10-18 20:59:28]

LGTM too, just a small comment.

https://codereview.chromium.org/2430663002/diff/1/third_party/WebKit/Source/c...
File third_party/WebKit/Source/core/layout/LayoutBox.h (right):

https://codereview.chromium.org/2430663002/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/layout/LayoutBox.h:1582: first =
first->nextInFlowSiblingBox();
I know I'm late but I think you don't need a loop here.
You could simply change the "while" for an "if",
as you're using nextInFlowSiblingBox().

[jfernandez, 2016-10-18 22:25:05]

https://codereview.chromium.org/2430663002/diff/1/third_party/WebKit/Source/c...
File third_party/WebKit/Source/core/layout/LayoutBox.h (right):

https://codereview.chromium.org/2430663002/diff/1/third_party/WebKit/Source/c...
third_party/WebKit/Source/core/layout/LayoutBox.h:1582: first =
first->nextInFlowSiblingBox();
On 2016/10/18 20:59:28, Manuel Rego wrote:
> I know I'm late but I think you don't need a loop here.
> You could simply change the "while" for an "if",
> as you're using nextInFlowSiblingBox().
>     

You are right, indeed. I can do that ASAP in a different
patch.