Remove form control related virtual methods from Element

Source/core/dom/Document.cpp

 /*
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  *           (C) 2006 Alexey Proskuryakov (ap@webkit.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009, 2011, 2012 Apple Inc. All rights reserved.
  * Copyright (C) 2008, 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  * Copyright (C) 2008, 2009, 2011, 2012 Google Inc. All rights reserved.
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies)
  * Copyright (C) Research In Motion Limited 2010-2011. All rights reserved.
@@ skipping 3345 matching lines @@
     // Remove focus from the existing focus node (if any)
     if (oldFocusedElement) {
         ASSERT(!oldFocusedElement->inDetach());
 
         if (oldFocusedElement->active())
             oldFocusedElement->setActive(false);
 
         oldFocusedElement->setFocus(false);
 
         // Dispatch a change event for text fields or textareas that have been edited
-        if (oldFocusedElement->wasChangedSinceLastFormControlChangeEvent())
-            oldFocusedElement->dispatchFormControlChangeEvent();
+        if (oldFocusedElement->isFormControlElement()) {

[tkent, 2014/01/30 01:38:50]

I don't like this change.
It increased virtual calls, and the function needs to know the special
requirement of HTMLFormControlElement.

Alternative idea is to move this code into
HTMLTextFormControlElement::setFocus().

[Inactive, 2014/01/30 01:57:22]

Did it really increase virtual calls? Sure isFormControlElement() is a new
virtual call but wasChangedSinceLastFormControlChangeEvent() is no longer one.
So it looks like it evens out.

I do agree with your second point though. The HTMLFormControlElement special
handling is now more explicit. Overriding Node::setFocus(bool) in
HTMLFormControlElement and moving the code there does sound like a better idea.
It seems setFocus() is only called from this method.

+            HTMLFormControlElement* formControlElement = toHTMLFormControlElement(oldFocusedElement);
+            if (formControlElement->wasChangedSinceLastFormControlChangeEvent())
+                formControlElement->dispatchFormControlChangeEvent();
+        }
 
         // Dispatch the blur event and let the node do any other blur related activities (important for text fields)
         // If page lost focus, blur event will have already been dispatched
         if (page() && (page()->focusController().isFocused())) {
             oldFocusedElement->dispatchBlurEvent(newFocusedElement.get());
 
             if (m_focusedElement) {
                 // handler shifted focus
                 focusChangeBlocked = true;
                 newFocusedElement = 0;
@@ skipping 1941 matching lines @@
     if (!page->focusController().isActive() || !page->focusController().isFocused())
         return false;
     if (Frame* focusedFrame = page->focusController().focusedFrame()) {
         if (focusedFrame->tree().isDescendantOf(frame()))
             return true;
     }
     return false;
 }
 
 } // namespace WebCore