Set ComputedStyle on Node and use that in buildOwnLayout()

third_party/WebKit/Source/core/dom/Node.h

Index: third_party/WebKit/Source/core/dom/Node.h
diff --git a/third_party/WebKit/Source/core/dom/Node.h b/third_party/WebKit/Source/core/dom/Node.h
index 9db76ee08e46e351d3bf6db6cf55660e2507b22a..12aebc414bd8bee0aff37a35ed195d260c8f20a4 100644
--- a/third_party/WebKit/Source/core/dom/Node.h
+++ b/third_party/WebKit/Source/core/dom/Node.h
@@ -522,7 +522,7 @@ public:
     // Note that if a Node has a layoutObject, it's parentNode is guaranteed to have one as well.
     LayoutObject* layoutObject() const
     {
-        if (hasRareData())
+        if (hasRareData() && hasLayoutObject())

[sashab, 2016/07/06 04:22:02]

Why the additional hasLayoutObject() here?

[Bugs Nash, 2016/07/06 04:30:42]

this isn't necessary

[nainar, 2016/07/06 04:51:53]

To make sure that we only read the LayoutObject in case we have specifically set
the LayoutObject and it does not contain some garbage value.

Two tests are failing here 

fast/forms/datalist/update-range-with-datalist.html
svg/custom/animate-target-removed-from-document.svg

[nainar, 2016/07/06 04:51:53]

See above. 

[Bugs Nash, 2016/07/06 05:00:21]

it shouldn't ever return garbage anyway - it should return nullptr if there is
no LayoutObject  on the rare data

use rareData() instead of m_data.m_rareData

[Bugs Nash, 2016/07/06 05:04:44]

oh nvm about the last comment - that's not part of this patch

[sashab, 2016/07/06 05:10:40]

I think you want if (hasRareData() && m_data.m_rareData->haslayoutObject())? 

[Bugs Nash, 2016/07/06 05:19:06]

I think just hasRareData() is sufficient

             return m_data.m_rareData->layoutObject();
         return hasLayoutObject() ? m_data.m_layoutObject : nullptr;
     }
@@ -569,6 +569,7 @@ public:
     // Wrapper for nodes that don't have a layoutObject, but still cache the style (like HTMLOptionElement).
     ComputedStyle* mutableComputedStyle() const;
     const ComputedStyle* computedStyle() const;
+    void setComputedStyle(PassRefPtr<ComputedStyle>);
     const ComputedStyle* parentComputedStyle() const;
 
     const ComputedStyle& computedStyleRef() const;