AX: Don't use listIndex in AXListBoxOption class.

* AXListBoxOption::isSelectedOptionActive()
  We don't need to compare indices. We can compare node pointers.

* AXListBoxOption::setSelected()
  We don't need to compute an optionIndex.  We can pass an HTMLOptionElement
  pointer directly by changing the argument type of accessKeySetSelectedIndex().
  This CL renames accessKeySetSelectedIndex() to selectOptionByAccessKey().

Now, we can remove AXListBoxOption::listBoxOptionIndex() and
HTMLSelectElement::listToOptionIndex().

Review-Url: https://codereview.chromium.org/2147963004
Cr-Commit-Position: refs/heads/master@{#405500}

third_party/WebKit/Source/core/html/HTMLOptionElement.cpp

@@ -171,7 +171,7 @@ void HTMLOptionElement::setText(const String &text, ExceptionState& exceptionSta
 void HTMLOptionElement::accessKeyAction(bool)
 {
     if (HTMLSelectElement* select = ownerSelectElement())
-        select->accessKeySetSelectedIndex(index());
+        select->selectOptionByAccessKey(this);
 }
 
 int HTMLOptionElement::index() const

third_party/WebKit/Source/core/html/HTMLSelectElement.cpp

@@ -1064,22 +1064,6 @@ int HTMLSelectElement::optionToListIndex(int optionIndex) const
     return -1;
 }
 
-int HTMLSelectElement::listToOptionIndex(int listIndex) const
-{
-    const ListItems& items = listItems();
-    if (!optionAtListIndex(listIndex))
-        return -1;
-
-    // Actual index of option not counting OPTGROUP entries that may be in list.
-    int optionIndex = 0;
-    for (int i = 0; i < listIndex; ++i) {
-        if (isHTMLOptionElement(*items[i]))
-            ++optionIndex;
-    }
-
-    return optionIndex;
-}
-
 void HTMLSelectElement::dispatchFocusEvent(Element* oldFocusedElement, WebFocusType type, InputDeviceCapabilities* sourceCapabilities)
 {
     // Save the selection so it can be compared to the new selection when
@@ -1717,14 +1701,13 @@ void HTMLSelectElement::typeAheadFind(KeyboardEvent* event)
         listBoxOnChange();
 }
 
-void HTMLSelectElement::accessKeySetSelectedIndex(int index)
+void HTMLSelectElement::selectOptionByAccessKey(HTMLOptionElement* option)
 {
     // First bring into focus the list box.
     if (!focused())
         accessKeyAction(false);
 
-    HTMLOptionElement* option = item(index);
-    if (!option)
+    if (!option || option->ownerSelectElement() != this)
         return;
     EventQueueScope scope;
     // If this index is already selected, unselect. otherwise update the

third_party/WebKit/Source/core/html/HTMLSelectElement.h

@@ -102,7 +102,7 @@ public:
     const ListItems& listItems() const;
 
     void accessKeyAction(bool sendMouseEvents) override;
-    void accessKeySetSelectedIndex(int);
+    void selectOptionByAccessKey(HTMLOptionElement*);
 
     void setOption(unsigned index, HTMLOptionElement*, ExceptionState&);
 
@@ -114,7 +114,6 @@ public:
 
     bool canSelectAll() const;
     void selectAll();
-    int listToOptionIndex(int listIndex) const;
     void listBoxOnChange();
     int optionToListIndex(int optionIndex) const;
     int activeSelectionEndListIndex() const;

third_party/WebKit/Source/modules/accessibility/AXListBoxOption.cpp

@@ -108,7 +108,7 @@ bool AXListBoxOption::isSelectedOptionActive() const
     if (!listBoxParentNode)
         return false;
 
-    return listBoxParentNode->activeSelectionEndListIndex() == listBoxOptionIndex();
+    return listBoxParentNode->activeSelectionEnd() == getNode();
 }
 
 bool AXListBoxOption::computeAccessibilityIsIgnored(IgnoredReasons* ignoredReasons) const
@@ -176,9 +176,7 @@ void AXListBoxOption::setSelected(bool selected)
     if ((isOptionSelected && selected) || (!isOptionSelected && !selected))
         return;
 
-    // Convert from the entire list index to the option index.
-    int optionIndex = selectElement->listToOptionIndex(listBoxOptionIndex());
-    selectElement->accessKeySetSelectedIndex(optionIndex);
+    selectElement->selectOptionByAccessKey(toHTMLOptionElement(getNode()));
 }
 
 HTMLSelectElement* AXListBoxOption::listBoxOptionParentNode() const
@@ -192,20 +190,4 @@ HTMLSelectElement* AXListBoxOption::listBoxOptionParentNode() const
     return 0;
 }
 
-int AXListBoxOption::listBoxOptionIndex() const
-{
-    HTMLSelectElement* selectElement = listBoxOptionParentNode();
-    if (!selectElement)
-        return -1;
-
-    const HeapVector<Member<HTMLElement>>& listItems = selectElement->listItems();
-    unsigned length = listItems.size();
-    for (unsigned i = 0; i < length; i++) {
-        if (listItems[i] == getNode())
-            return i;
-    }
-
-    return -1;
-}
-
 } // namespace blink

third_party/WebKit/Source/modules/accessibility/AXListBoxOption.h

@@ -62,7 +62,6 @@ private:
     bool computeAccessibilityIsIgnored(IgnoredReasons* = nullptr) const override;
 
     HTMLSelectElement* listBoxOptionParentNode() const;
-    int listBoxOptionIndex() const;
     bool isParentPresentationalRole() const;
 };