Add function to write paint property tree graph in dot format.

Add function to write paint property tree graph in dot format.

If the output is saved to a file properties.txt, you can generate a
visual representation using dot:

$ dot -Tsvg properties.txt > properties.svg

Sample output:

http://jsbin.com/jajuyuyixo/edit?output

R=pdr@chromium.org,wangxianzhu@chromium.org
BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Committed: https://crrev.com/1aeacecc9790e6e1f767d71fe665daea5822a260
Cr-Commit-Position: refs/heads/master@{#415665}

[szager1, 2016-08-18 22:10:19]

Description was changed from

==========
Add function to write paint property tree graph in dot format.

If the output is saved to a file properties.txt, you can generate a
visual representation using dot:

$ dot -Tsvg properties.txt > properties.svg

Sample output:

http://jsbin.com/jajuyuyixo/edit?output

R=pdr@chromium.org,wangxianzhu@chromium.org
BUG=
==========

to

==========
Add function to write paint property tree graph in dot format.

If the output is saved to a file properties.txt, you can generate a
visual representation using dot:

$ dot -Tsvg properties.txt > properties.svg

Sample output:

http://jsbin.com/jajuyuyixo/edit?output

R=pdr@chromium.org,wangxianzhu@chromium.org
BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

[Xianzhu, 2016-08-19 04:08:17]

https://codereview.chromium.org/2252273006/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.cpp (right):

https://codereview.chromium.org/2252273006/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.cpp:401: continue;
It looks fragile to depend on the tree walk order and replicate the logic in
PrePaintTreeWalk. The logic in PropertyTreePrinter::collectAllPropertyNodes() is
tree-walk-order neutral. Can you call that function to collect nodes then print
the collected nodes in dot format?

[szager1, 2016-08-19 04:52:31]

https://codereview.chromium.org/2252273006/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.cpp (right):

https://codereview.chromium.org/2252273006/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.cpp:401: continue;
On 2016/08/19 04:08:17, Xianzhu wrote:
> It looks fragile to depend on the tree walk order and replicate the logic in
> PrePaintTreeWalk. The logic in PropertyTreePrinter::collectAllPropertyNodes()
is
> tree-walk-order neutral. Can you call that function to collect nodes then
print
> the collected nodes in dot format?

collectPropertyNodes has a few incompatibilities:

- It doesn't preserve the ownership relationship between LayoutObject and paint
properties, or any layout tree information.
- It doesn't preserve the FrameView -> LayoutPart relationship for iframes.
- It's only designed to collect one type of paint property (transform OR clip OR
effect); this code collects all of them.

I'm not against combining the logic, but I didn't want to completely tear up the
existing PropertyTreePrinter code to do this.

[Xianzhu, 2016-08-20 23:06:48]

https://codereview.chromium.org/2252273006/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.cpp (right):

https://codereview.chromium.org/2252273006/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.cpp:401: continue;
On 2016/08/19 04:52:31, szager1 wrote:
> On 2016/08/19 04:08:17, Xianzhu wrote:
> > It looks fragile to depend on the tree walk order and replicate the logic in
> > PrePaintTreeWalk. The logic in
PropertyTreePrinter::collectAllPropertyNodes()
> is
> > tree-walk-order neutral. Can you call that function to collect nodes then
> print
> > the collected nodes in dot format?
> 
> collectPropertyNodes has a few incompatibilities:
> 
> - It doesn't preserve the ownership relationship between LayoutObject and
paint
> properties, or any layout tree information.
> - It doesn't preserve the FrameView -> LayoutPart relationship for iframes.
> - It's only designed to collect one type of paint property (transform OR clip
OR
> effect); this code collects all of them.
> 
> I'm not against combining the logic, but I didn't want to completely tear up
the
> existing PropertyTreePrinter code to do this.

OK. What if you remove the above two lines? If the above 2 lines are really
needed, you also need to copy the logic to walk through the column-span
placeholder like
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/paint/Pre....
Otherwise the result tree will miss the nodes of column spans.

[szager1, 2016-08-31 00:40:12]

https://codereview.chromium.org/2252273006/diff/20001/third_party/WebKit/Sour...
File third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.cpp (right):

https://codereview.chromium.org/2252273006/diff/20001/third_party/WebKit/Sour...
third_party/WebKit/Source/core/paint/PaintPropertyTreePrinter.cpp:401: continue;
On 2016/08/20 23:06:48, Xianzhu wrote:
> On 2016/08/19 04:52:31, szager1 wrote:
> > On 2016/08/19 04:08:17, Xianzhu wrote:
> > > It looks fragile to depend on the tree walk order and replicate the logic
in
> > > PrePaintTreeWalk. The logic in
> PropertyTreePrinter::collectAllPropertyNodes()
> > is
> > > tree-walk-order neutral. Can you call that function to collect nodes then
> > print
> > > the collected nodes in dot format?
> > 
> > collectPropertyNodes has a few incompatibilities:
> > 
> > - It doesn't preserve the ownership relationship between LayoutObject and
> paint
> > properties, or any layout tree information.
> > - It doesn't preserve the FrameView -> LayoutPart relationship for iframes.
> > - It's only designed to collect one type of paint property (transform OR
clip
> OR
> > effect); this code collects all of them.
> > 
> > I'm not against combining the logic, but I didn't want to completely tear up
> the
> > existing PropertyTreePrinter code to do this.
> 
> OK. What if you remove the above two lines? If the above 2 lines are really
> needed, you also need to copy the logic to walk through the column-span
> placeholder like
>
https://cs.chromium.org/chromium/src/third_party/WebKit/Source/core/paint/Pre....
> Otherwise the result tree will miss the nodes of column spans.

Yes, you're right, these two lines are unnecessary.  I removed them.

[Xianzhu, 2016-08-31 05:23:59]

lgtm

[szager1, 2016-08-31 15:39:27]

The CQ bit was checked by szager@chromium.org

[commit-bot: I haz the power, 2016-08-31 15:39:52]

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

[szager1, 2016-08-31 15:46:20]

The CQ bit was unchecked by szager@chromium.org

[szager1, 2016-08-31 15:50:07]

The CQ bit was checked by szager@chromium.org

[szager1, 2016-08-31 15:50:08]

The patchset sent to the CQ was uploaded after l-g-t-m from
wangxianzhu@chromium.org
Link to the patchset: https://codereview.chromium.org/2252273006/#ps60001
(title: "Emit parent/owner edges for degenerate transforms")

[commit-bot: I haz the power, 2016-08-31 15:50:27]

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, 2016-08-31 17:11:37]

Committed patchset #4 (id:60001)

[commit-bot: I haz the power, 2016-08-31 17:16:22]

Description was changed from

==========
Add function to write paint property tree graph in dot format.

If the output is saved to a file properties.txt, you can generate a
visual representation using dot:

$ dot -Tsvg properties.txt > properties.svg

Sample output:

http://jsbin.com/jajuyuyixo/edit?output

R=pdr@chromium.org,wangxianzhu@chromium.org
BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
==========

to

==========
Add function to write paint property tree graph in dot format.

If the output is saved to a file properties.txt, you can generate a
visual representation using dot:

$ dot -Tsvg properties.txt > properties.svg

Sample output:

http://jsbin.com/jajuyuyixo/edit?output

R=pdr@chromium.org,wangxianzhu@chromium.org
BUG=
CQ_INCLUDE_TRYBOTS=master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2

Committed: https://crrev.com/1aeacecc9790e6e1f767d71fe665daea5822a260
Cr-Commit-Position: refs/heads/master@{#415665}
==========

[commit-bot: I haz the power, 2016-08-31 17:16:24]

Patchset 4 (id:??) landed as
https://crrev.com/1aeacecc9790e6e1f767d71fe665daea5822a260
Cr-Commit-Position: refs/heads/master@{#415665}