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

Source/core/html/BaseButtonInputType.cpp

Index: Source/core/html/BaseButtonInputType.cpp
diff --git a/Source/core/html/BaseButtonInputType.cpp b/Source/core/html/BaseButtonInputType.cpp
index 75f97ec243ae7640b138cf75b3a8e3a6c63e590c..e3b6b296e7c6050d49d4c630e30853518b54bac7 100644
--- a/Source/core/html/BaseButtonInputType.cpp
+++ b/Source/core/html/BaseButtonInputType.cpp
@@ -41,6 +41,11 @@ namespace WebCore {
 
 using namespace HTMLNames;
 
+BaseButtonInputType::BaseButtonInputType(const Handle<HTMLInputElement>& element)
+    : BaseClickableWithKeyInputType(element)
+{
+}
+
 bool BaseButtonInputType::shouldSaveAndRestoreFormControlState() const
 {
     return false;
@@ -54,7 +59,7 @@ bool BaseButtonInputType::appendFormData(FormDataList&, bool) const
 
 RenderObject* BaseButtonInputType::createRenderer(RenderArena* arena, RenderStyle*) const
 {
-    return new (arena) RenderButton(element());
+    return new (arena) RenderButton(Handle<HTMLInputElement>(element()).raw());
 }
 
 bool BaseButtonInputType::storesValueSeparateFromAttribute()