Introduce toHTMLInputElement(Node*), and use it.

Source/core/accessibility/AccessibilityRenderObject.cpp

Index: Source/core/accessibility/AccessibilityRenderObject.cpp
diff --git a/Source/core/accessibility/AccessibilityRenderObject.cpp b/Source/core/accessibility/AccessibilityRenderObject.cpp
index 4c3e46c034abee7e96ce117976f9a93f5100acba..3d75a94926c03e279e9aac68b9fde11343ed4c07 100644
--- a/Source/core/accessibility/AccessibilityRenderObject.cpp
+++ b/Source/core/accessibility/AccessibilityRenderObject.cpp
@@ -391,7 +391,7 @@ AccessibilityRole AccessibilityRenderObject::determineAccessibilityRole()
         return TextAreaRole;
 
     if (node && node->hasTagName(inputTag)) {
-        HTMLInputElement* input = static_cast<HTMLInputElement*>(node);
+        HTMLInputElement* input = toHTMLInputElement(node);
         if (input->isCheckbox())
             return CheckBoxRole;
         if (input->isRadioButton())
@@ -528,7 +528,7 @@ bool AccessibilityRenderObject::isAttachment() const
 bool AccessibilityRenderObject::isFileUploadButton() const
 {
     if (m_renderer && m_renderer->node() && m_renderer->node()->hasTagName(inputTag)) {
-        HTMLInputElement* input = static_cast<HTMLInputElement*>(m_renderer->node());
+        HTMLInputElement* input = toHTMLInputElement(m_renderer->node());
         return input->isFileUpload();
     }
 
@@ -1109,7 +1109,7 @@ KURL AccessibilityRenderObject::url() const
         return static_cast<HTMLImageElement*>(m_renderer->node())->src();
 
     if (isInputImage())
-        return static_cast<HTMLInputElement*>(m_renderer->node())->src();
+        return toHTMLInputElement(m_renderer->node())->src();
 
     return KURL();
 }
@@ -2066,7 +2066,7 @@ void AccessibilityRenderObject::setValue(const String& string)
     // FIXME: Do we want to do anything here for ARIA textboxes?
     if (renderer->isTextField()) {
         // FIXME: This is not safe!  Other elements could have a TextField renderer.
-        static_cast<HTMLInputElement*>(element)->setValue(string);
+        toHTMLInputElement(element)->setValue(string);
     } else if (renderer->isTextArea()) {
         // FIXME: This is not safe!  Other elements could have a TextArea renderer.
         static_cast<HTMLTextAreaElement*>(element)->setValue(string);
@@ -2683,7 +2683,7 @@ void AccessibilityRenderObject::addRadioButtonGroupMembers(AccessibilityChildren
     if (!node || !node->hasTagName(inputTag))
         return;
 
-    HTMLInputElement* input = static_cast<HTMLInputElement*>(node);
+    HTMLInputElement* input = toHTMLInputElement(node);
     // if there's a form, then this is easy
     if (input->form()) {
         Vector<RefPtr<Node> > formElements;
@@ -2700,7 +2700,7 @@ void AccessibilityRenderObject::addRadioButtonGroupMembers(AccessibilityChildren
         unsigned len = list->length();
         for (unsigned i = 0; i < len; ++i) {
             if (list->item(i)->hasTagName(inputTag)) {
-                HTMLInputElement* associateElement = static_cast<HTMLInputElement*>(list->item(i));
+                HTMLInputElement* associateElement = toHTMLInputElement(list->item(i));
                 if (associateElement->isRadioButton() && associateElement->name() == input->name()) {
                     if (AccessibilityObject* object = axObjectCache()->getOrCreate(associateElement))
                         linkedUIElements.append(object);
@@ -2977,7 +2977,7 @@ void AccessibilityRenderObject::addTextFieldChildren()
     if (!node || !node->hasTagName(inputTag))
         return;
 
-    HTMLInputElement* input = static_cast<HTMLInputElement*>(node);
+    HTMLInputElement* input = toHTMLInputElement(node);
     HTMLElement* spinButtonElement = input->innerSpinButtonElement();
     if (!spinButtonElement || !spinButtonElement->isSpinButtonElement())
         return;