Delay construction of StyleResolverState until after style sharing.

Source/core/css/resolver/StyleResolverState.cpp

Index: Source/core/css/resolver/StyleResolverState.cpp
diff --git a/Source/core/css/resolver/StyleResolverState.cpp b/Source/core/css/resolver/StyleResolverState.cpp
index 798235740821e8c7b162749a717639b1cfa21564..66401bf51144299be70cc2386d9c1a6a46cb0f58 100644
--- a/Source/core/css/resolver/StyleResolverState.cpp
+++ b/Source/core/css/resolver/StyleResolverState.cpp
@@ -29,8 +29,8 @@
 
 namespace blink {
 
-StyleResolverState::StyleResolverState(Document& document, Element* element, RenderStyle* parentStyle)
-    : m_elementContext(element ? ElementResolveContext(*element) : ElementResolveContext(document))
+StyleResolverState::StyleResolverState(Document& document, const ElementResolveContext& elementContext, RenderStyle* parentStyle)
+    : m_elementContext(elementContext)
     , m_document(document)
     , m_style(nullptr)
     , m_parentStyle(parentStyle)
@@ -39,13 +39,18 @@ StyleResolverState::StyleResolverState(Document& document, Element* element, Ren
     , m_fontBuilder(document)
     , m_styleMap(*this, m_elementStyleResources)
 {
-    if (!parentStyle && m_elementContext.parentNode())
-        m_parentStyle = m_elementContext.parentNode()->renderStyle();
+    if (!m_parentStyle)
+        m_parentStyle = m_elementContext.parentStyle();
 
     ASSERT(document.isActive());
     m_elementStyleResources.setDeviceScaleFactor(document.frameHost()->deviceScaleFactor());
 }
 
+StyleResolverState::StyleResolverState(Document& document, Element* element, RenderStyle* parentStyle)
+    : StyleResolverState(document, element ? ElementResolveContext(*element) : ElementResolveContext(document), parentStyle)
+{
+}
+
 StyleResolverState::~StyleResolverState()
 {
 }