[oilpan] Completely move HTMLFormControlElement's hierarchy to the managed heap

Source/core/html/HTMLElement.cpp

Index: Source/core/html/HTMLElement.cpp
diff --git a/Source/core/html/HTMLElement.cpp b/Source/core/html/HTMLElement.cpp
index 04ce873d29c837959c01e1b77160cb554c321d39..598b3df66ce7edeaa0419f72e56c303bc4e59e27 100644
--- a/Source/core/html/HTMLElement.cpp
+++ b/Source/core/html/HTMLElement.cpp
@@ -847,11 +847,11 @@ TextDirection HTMLElement::directionalityIfhasDirAutoAttribute(bool& isAuto) con
 TextDirection HTMLElement::directionality(Node** strongDirectionalityTextNode) const
 {
     if (isHTMLTextFormControlElement(this)) {
-        HTMLTextFormControlElement* textElement = toHTMLTextFormControlElement(const_cast<HTMLElement*>(this));
+        Handle<HTMLTextFormControlElement> textElement = toHTMLTextFormControlElement(const_cast<HTMLElement*>(this));
         bool hasStrongDirectionality;
         Unicode::Direction textDirection = textElement->value().defaultWritingDirection(&hasStrongDirectionality);
         if (strongDirectionalityTextNode)
-            *strongDirectionalityTextNode = hasStrongDirectionality ? textElement : 0;
+            *strongDirectionalityTextNode = hasStrongDirectionality ? textElement.raw() : 0;
         return (textDirection == Unicode::LeftToRight) ? LTR : RTL;
     }