Add Autofill preview support for <select> input fields

Source/core/html/HTMLSelectElement.cpp

 /*
  * Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
  * Copyright (C) 1999 Lars Knoll (knoll@kde.org)
  *           (C) 1999 Antti Koivisto (koivisto@kde.org)
  *           (C) 2001 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2004, 2005, 2006, 2007, 2009, 2010, 2011 Apple Inc. All rights reserved.
  *           (C) 2006 Alexey Proskuryakov (ap@nypop.com)
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2009 Torch Mobile Inc. All rights reserved. (http://www.torchmobile.com/)
  *
@@ skipping 235 matching lines @@
                 setSelectedIndex(optionIndex);
                 return;
             }
             optionIndex++;
         }
     }
 
     setSelectedIndex(-1);
 }
 
+String HTMLSelectElement::suggestedValue() const
+{
+    const Vector<HTMLElement*>& items = listItems();
+    for (unsigned i = 0; i < items.size(); i++) {

[tkent, 2014/03/14 00:06:41]

We prefer ++i.

[ziran.sun, 2014/03/14 11:32:37]

Done.

+        if (items[i]->hasLocalName(optionTag) && toHTMLOptionElement(items[i])->value() == m_suggestedValue)
+            return m_suggestedValue;
+    }
+    return "";
+}
+
+void HTMLSelectElement::setSuggestedValue(const String& value)
+{
+    m_suggestedValue = value;
+
+    if (value.isNull()) {
+        setSuggestedIndex(-1);
+        return;
+    }
+
+    const Vector<HTMLElement*>& items = listItems();
+    unsigned optionIndex = 0;
+    for (unsigned i = 0; i < items.size(); i++) {

[tkent, 2014/03/14 00:06:41]

Ditto.

[ziran.sun, 2014/03/14 11:32:37]

Done.

+        if (items[i]->hasLocalName(optionTag)) {
+            if (toHTMLOptionElement(items[i])->value() == value) {
+                setSuggestedIndex(optionIndex);
+                return;
+            }
+            optionIndex++;
+        }
+    }
+
+    setSuggestedIndex(-1);
+}
+
 bool HTMLSelectElement::isPresentationAttribute(const QualifiedName& name) const
 {
     if (name == alignAttr) {
         // Don't map 'align' attribute. This matches what Firefox, Opera and IE do.
         // See http://bugs.webkit.org/show_bug.cgi?id=12072
         return false;
     }
 
     return HTMLFormControlElementWithState::isPresentationAttribute(name);
 }
@@ skipping 522 matching lines @@
     }
 
     return -1;
 }
 
 void HTMLSelectElement::setSelectedIndex(int index)
 {
     selectOption(index, DeselectOtherOptions);
 }
 
+int HTMLSelectElement::suggestedIndex() const
+{
+    return m_suggestedIndex;
+}
+
+void HTMLSelectElement::setSuggestedIndex(int suggestedIndex)
+{
+    m_suggestedIndex = suggestedIndex;
+
+    if (RenderObject* renderer = this->renderer())  {
+        renderer->updateFromElement();
+        if (renderer->isListBox())
+            toRenderListBox(renderer)->scrollToRevealElementAtListIndex(suggestedIndex);
+    }
+
+    setNeedsValidityCheck();

[tkent, 2014/03/14 00:06:41]

I don't think validity check is necessary. Updating suggestion value/index
should not affect element validity.

[ziran.sun, 2014/03/14 11:32:37]

Done.

+}
+
 void HTMLSelectElement::optionSelectionStateChanged(HTMLOptionElement* option, bool optionIsSelected)
 {
     ASSERT(option->ownerSelectElement() == this);
     if (optionIsSelected)
         selectOption(option->index());
     else if (!usesMenuList() || multiple())
         selectOption(-1);
     else
         selectOption(nextSelectableListIndex(-1));
 }
@@ skipping 756 matching lines @@
 {
     return true;
 }
 
 bool HTMLSelectElement::supportsAutofocus() const
 {
     return true;
 }
 
 } // namespace