HTMLSelectElement does not include selected index/indices while saving state

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 1021 matching lines @@
     const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& items = listItems();
     size_t length = items.size();
     FormControlState state;
     for (unsigned i = 0; i < length; ++i) {
         if (!isHTMLOptionElement(*items[i]))
             continue;
         HTMLOptionElement* option = toHTMLOptionElement(items[i]);
         if (!option->selected())
             continue;
         state.append(option->value());
+        state.append(String::number(i));
         if (!multiple())
             break;
     }
     return state;
 }
 
 size_t HTMLSelectElement::searchOptionsForValue(const String& value, size_t listIndexStart, size_t listIndexEnd) const
 {
     const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& items = listItems();
     size_t loopEndIndex = std::min(items.size(), listIndexEnd);
     for (size_t i = listIndexStart; i < loopEndIndex; ++i) {
         if (!isHTMLOptionElement(items[i]))
             continue;
         if (toHTMLOptionElement(items[i])->value() == value)
             return i;
     }
     return kNotFound;
 }
 
+String HTMLSelectElement::valueAtIndex(size_t index) const
+{
+    const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& items = listItems();
+    return index < items.size() && isHTMLOptionElement(items[index]) ? toHTMLOptionElement(items[index])->value() : WTF::emptyString();
+}
+
 void HTMLSelectElement::restoreFormControlState(const FormControlState& state)
 {
     recalcListItems();
 
     const WillBeHeapVector<RawPtrWillBeMember<HTMLElement> >& items = listItems();
     size_t itemsSize = items.size();
     if (!itemsSize)
         return;
 
     for (size_t i = 0; i < itemsSize; ++i) {
         if (!isHTMLOptionElement(items[i]))
             continue;
         toHTMLOptionElement(items[i])->setSelectedState(false);
     }
 
+    // The saved state should have at least one value and an index.
+    ASSERT(state.valueSize() >= 2);
     if (!multiple()) {
-        size_t foundIndex = searchOptionsForValue(state[0], 0, itemsSize);
-        if (foundIndex != kNotFound)
-            toHTMLOptionElement(items[foundIndex])->setSelectedState(true);
+        size_t index = state[1].toUInt();
+        if (index < itemsSize && isHTMLOptionElement(items[index]) && valueAtIndex(index) == state[0]) {

[tkent, 2014/09/10 23:35:50]

|index < items.size() && isHTMLOptionElement(items[index])| in valueAtIndex() is
redundant and should be removed.  valueAtIndex() would be helpless, and we
should remove valueAtIndex() entirely.

[spartha, 2014/09/12 05:46:08]

Done.

+            toHTMLOptionElement(items[index])->setSelectedState(true);
+        } else {
+            size_t foundIndex = searchOptionsForValue(state[0], 0, itemsSize);
+            if (foundIndex != kNotFound)
+                toHTMLOptionElement(items[foundIndex])->setSelectedState(true);
+        }
     } else {
         size_t startIndex = 0;
-        for (size_t i = 0; i < state.valueSize(); ++i) {
+        for (size_t i = 0; i < state.valueSize(); i+= 2) {
             const String& value = state[i];
-            size_t foundIndex = searchOptionsForValue(value, startIndex, itemsSize);
-            if (foundIndex == kNotFound)
-                foundIndex = searchOptionsForValue(value, 0, startIndex);
-            if (foundIndex == kNotFound)
-                continue;
-            toHTMLOptionElement(items[foundIndex])->setSelectedState(true);
-            startIndex = foundIndex + 1;
+            const size_t index = state[i + 1].toUInt();
+            if (index < itemsSize && isHTMLOptionElement(items[index]) && valueAtIndex(index) == value) {
+                toHTMLOptionElement(items[index])->setSelectedState(true);
+                startIndex = index + 1;
+            } else {
+                size_t foundIndex = searchOptionsForValue(value, startIndex, itemsSize);
+                if (foundIndex == kNotFound)
+                    foundIndex = searchOptionsForValue(value, 0, startIndex);
+                if (foundIndex == kNotFound)
+                    continue;
+                toHTMLOptionElement(items[foundIndex])->setSelectedState(true);
+                startIndex = foundIndex + 1;
+            }
         }
     }
 
     setOptionsChangedOnRenderer();
     setNeedsValidityCheck();
 }
 
 void HTMLSelectElement::parseMultipleAttribute(const AtomicString& value)
 {
     m_multiple = !value.isNull();
@@ skipping 639 matching lines @@
     int focusedIndex = activeSelectionEndListIndex();
     if (focusedIndex < 0)
         focusedIndex = firstSelectableListIndex();
     if (focusedIndex < 0)
         return nullptr;
     HTMLElement* focused = listItems()[focusedIndex];
     return isHTMLOptionElement(focused) ? toHTMLOptionElement(focused) : nullptr;
 }
 
 } // namespace