Remove support for anonymous deprecated flexboxes.

Source/core/rendering/RenderDeprecatedFlexibleBox.cpp

Index: Source/core/rendering/RenderDeprecatedFlexibleBox.cpp
diff --git a/Source/core/rendering/RenderDeprecatedFlexibleBox.cpp b/Source/core/rendering/RenderDeprecatedFlexibleBox.cpp
index a68fafc730770b264594c8f7b3c523c4095d39d3..8044de9b77d16e47abc1938b750528cff4a50e7d 100644
--- a/Source/core/rendering/RenderDeprecatedFlexibleBox.cpp
+++ b/Source/core/rendering/RenderDeprecatedFlexibleBox.cpp
@@ -119,8 +119,8 @@ private:
     int m_ordinalIteration;
 };
 
-RenderDeprecatedFlexibleBox::RenderDeprecatedFlexibleBox(Element* element)
-    : RenderBlock(element)
+RenderDeprecatedFlexibleBox::RenderDeprecatedFlexibleBox(Element& element)
+    : RenderBlock(&element)
 {
     ASSERT(!childrenInline());
     m_stretchingChildren = false;
@@ -139,13 +139,6 @@ RenderDeprecatedFlexibleBox::~RenderDeprecatedFlexibleBox()
 {
 }
 
-RenderDeprecatedFlexibleBox* RenderDeprecatedFlexibleBox::createAnonymous(Document* document)
-{
-    RenderDeprecatedFlexibleBox* renderer = new RenderDeprecatedFlexibleBox(0);
-    renderer->setDocumentForAnonymous(document);
-    return renderer;
-}
-
 static LayoutUnit marginWidthForChild(RenderBox* child)
 {
     // A margin basically has three types: fixed, percentage, and auto (variable).