Add ComposedTreeTraversal::lastWithin/lastWithinOrSelf

Add ComposedTreeTraversal::lastWithin/lastWithinOrSelf

This patch adds ComposedTreeTraversal::lastWithin/lastWithinOrSelf which
are counterparts of NodeTraversal::lastWithin/lastWithinOrSelf.

This patch is result of collaboration work with yosin@chromium.org
for selection of web components.

BUG=275851
TEST=./out/Debug/webkit_unit_tests --gtest_filter=ComposedTreeTraversal*

Committed: https://src.chromium.org/viewvc/blink?view=rev&revision=192583

[hajimehoshi, 2015-03-25 10:36:48]

hajimehoshi@chromium.org changed reviewers:
+ hayato@chromium.org

[hajimehoshi, 2015-03-25 10:36:49]

PTAL

[hayato, 2015-03-26 03:28:27]

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
File Source/core/dom/shadow/ComposedTreeTraversal.cpp (right):

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
Source/core/dom/shadow/ComposedTreeTraversal.cpp:245: {
Could you insert assertions like other public functions do?
I'd like to make sure all public functions assert the input and the output.

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
File Source/core/dom/shadow/ComposedTreeTraversal.h (right):

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
Source/core/dom/shadow/ComposedTreeTraversal.h:99: static Node&
lastWithinOrSelf(Node&);
Input |Node&| can't be |const Node&|?

I guess our concern is the case where it returns self, however, 
I think it's okay that |const Node&| will be discarded for self in this case in
practical.

[hajimehoshi, 2015-03-26 03:37:18]

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
File Source/core/dom/shadow/ComposedTreeTraversal.h (right):

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
Source/core/dom/shadow/ComposedTreeTraversal.h:99: static Node&
lastWithinOrSelf(Node&);
On 2015/03/26 03:28:27, hayato wrote:
> Input |Node&| can't be |const Node&|?
> 
> I guess our concern is the case where it returns self, however, 
> I think it's okay that |const Node&| will be discarded for self in this case
in
> practical.

As you mentioned, I was worried the case when this function returns the argument
itself. You mean I can use const_cast in this case? I'll try to do that.

[hayato, 2015-03-26 03:39:14]

On 2015/03/26 03:37:18, hajimehoshi wrote:
>
https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
> File Source/core/dom/shadow/ComposedTreeTraversal.h (right):
> 
>
https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
> Source/core/dom/shadow/ComposedTreeTraversal.h:99: static Node&
> lastWithinOrSelf(Node&);
> On 2015/03/26 03:28:27, hayato wrote:
> > Input |Node&| can't be |const Node&|?
> > 
> > I guess our concern is the case where it returns self, however, 
> > I think it's okay that |const Node&| will be discarded for self in this case
> in
> > practical.
> 
> As you mentioned, I was worried the case when this function returns the
argument
> itself. You mean I can use const_cast in this case? I'll try to do that.

Yes, we have to use const_cast for self. I guess some guys don't like it,
however, I think it doesn't matter in practical.

[hajimehoshi, 2015-03-26 03:43:26]

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
File Source/core/dom/shadow/ComposedTreeTraversal.cpp (right):

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
Source/core/dom/shadow/ComposedTreeTraversal.cpp:245: {
On 2015/03/26 03:28:27, hayato wrote:
> Could you insert assertions like other public functions do?
> I'd like to make sure all public functions assert the input and the output.

Done.

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
File Source/core/dom/shadow/ComposedTreeTraversal.h (right):

https://codereview.chromium.org/1030153002/diff/1/Source/core/dom/shadow/Comp...
Source/core/dom/shadow/ComposedTreeTraversal.h:99: static Node&
lastWithinOrSelf(Node&);
On 2015/03/26 03:37:18, hajimehoshi wrote:
> On 2015/03/26 03:28:27, hayato wrote:
> > Input |Node&| can't be |const Node&|?
> > 
> > I guess our concern is the case where it returns self, however, 
> > I think it's okay that |const Node&| will be discarded for self in this case
> in
> > practical.
> 
> As you mentioned, I was worried the case when this function returns the
argument
> itself. You mean I can use const_cast in this case? I'll try to do that.

Done.

[hayato, 2015-03-26 03:48:45]

https://codereview.chromium.org/1030153002/diff/20001/Source/core/dom/shadow/...
File Source/core/dom/shadow/ComposedTreeTraversal.cpp (right):

https://codereview.chromium.org/1030153002/diff/20001/Source/core/dom/shadow/...
Source/core/dom/shadow/ComposedTreeTraversal.cpp:247: Node* descendant =
lastChild(current);
Could you use travrseLastChild instead of lastChild() in this function?

And insert assertPostCondtion(descendant) at last.

[hajimehoshi, 2015-03-26 03:56:12]

https://codereview.chromium.org/1030153002/diff/20001/Source/core/dom/shadow/...
File Source/core/dom/shadow/ComposedTreeTraversal.cpp (right):

https://codereview.chromium.org/1030153002/diff/20001/Source/core/dom/shadow/...
Source/core/dom/shadow/ComposedTreeTraversal.cpp:247: Node* descendant =
lastChild(current);
On 2015/03/26 03:48:44, hayato wrote:
> Could you use travrseLastChild instead of lastChild() in this function?
> 
> And insert assertPostCondtion(descendant) at last.

Done.

Besides, renamed |current| to |node| for consistency.

[hayato, 2015-03-26 04:25:33]

lgtm

[hajimehoshi, 2015-03-26 04:49:54]

The CQ bit was checked by hajimehoshi@chromium.org

[commit-bot: I haz the power, 2015-03-26 04:50:19]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1030153002/40001

[commit-bot: I haz the power, 2015-03-26 06:25:44]

Committed patchset #3 (id:40001) as
https://src.chromium.org/viewvc/blink?view=rev&revision=192583