Revert of Convert first letter into a pseudo element.

Source/core/dom/RenderTreeBuilder.h

Index: Source/core/dom/RenderTreeBuilder.h
diff --git a/Source/core/dom/RenderTreeBuilder.h b/Source/core/dom/RenderTreeBuilder.h
index dc7a379bd0ffce1d56ec1b5c95f5b3dd4824ea87..30d639c4d921dfedc25c9f910104ecda34f7adc8 100644
--- a/Source/core/dom/RenderTreeBuilder.h
+++ b/Source/core/dom/RenderTreeBuilder.h
@@ -27,21 +27,36 @@
 #define RenderTreeBuilder_h
 
 #include "core/dom/Document.h"
-#include "core/dom/FirstLetterPseudoElement.h"
 #include "core/dom/Node.h"
 #include "core/dom/NodeRenderingTraversal.h"
-#include "core/rendering/RenderObject.h"
 #include "wtf/RefPtr.h"
 
 namespace blink {
 
 class ContainerNode;
+class RenderObject;
 class RenderStyle;
 
 class RenderTreeBuilder {
     STACK_ALLOCATED();
 public:
-    RenderTreeBuilder(Node*, RenderStyle*);
+    RenderTreeBuilder(Node* node, RenderStyle* style)
+        : m_node(node)
+        , m_renderingParent(nullptr)
+        , m_style(style)
+    {
+        ASSERT(!node->renderer());
+        ASSERT(node->needsAttach());
+        ASSERT(node->document().inStyleRecalc());
+
+        // FIXME: We should be able to ASSERT(node->inActiveDocument()) but childrenChanged is called
+        // before ChildNodeInsertionNotifier in ContainerNode's methods and some implementations
+        // will trigger a layout inside childrenChanged.
+        // Mainly HTMLTextAreaElement::childrenChanged calls HTMLTextFormControlElement::setSelectionRange
+        // which does an updateLayoutIgnorePendingStylesheets.
+
+        m_renderingParent = NodeRenderingTraversal::parent(node, &m_parentDetails);
+    }
 
     void createRendererForTextIfNeeded();
     void createRendererForElementIfNeeded();
@@ -53,7 +68,7 @@ private:
     RenderStyle& style() const;
 
     RawPtrWillBeMember<Node> m_node;
-    RawPtrWillBeMember<RenderObject> m_renderingParent;
+    RawPtrWillBeMember<ContainerNode> m_renderingParent;
     NodeRenderingTraversal::ParentDetails m_parentDetails;
     mutable RefPtr<RenderStyle> m_style;
 };