SELECT element: Add HTMLSelectElement::selectedListIndex().

We had multiple instances of |optionToListIndex(selectedIndex())|, which causes two iterations over OPTIONs. selectedListIndex() returns the same value, but is more efficient. Review-Url: https://codereview.chromium.org/2149763003 Cr-Commit-Position: refs/heads/master@{#405508}

SELECT element: Add HTMLSelectElement::selectedListIndex().
We had multiple instances of |optionToListIndex(selectedIndex())|, which causes two iterations over OPTIONs. selectedListIndex() returns the same value, but is more efficient. Review-Url: https://codereview.chromium.org/2149763003 Cr-Commit-Position: refs/heads/master@{#405508}
c97868e4 · tkent · Commit bot · 5897d75b · c97868e4 · c97868e4
Commit c97868e4 authored Jul 14, 2016 by tkent Committed by Commit bot Jul 14, 2016
4 changed files
--- a/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
+++ b/third_party/WebKit/Source/core/html/HTMLSelectElement.cpp
@@ -873,6 +873,17 @@ void HTMLSelectElement::setSelectedIndex(int index)
    selectOption(item(index), DeselectOtherOptions | MakeOptionDirty);
 }

+int HTMLSelectElement::selectedListIndex() const
+{
+    int index = 0;
+    for (const auto& item : listItems()) {
+        if (isHTMLOptionElement(item) && toHTMLOptionElement(item)->selected())
+            return index;
+        ++index;
+    }
+    return -1;
+}
+
 void HTMLSelectElement::setSuggestedOption(HTMLOptionElement* option)
 {
    if (m_suggestedOption == option)
@@ -1674,7 +1685,7 @@ HTMLOptionElement* HTMLSelectElement::lastSelectedOption() const

 int HTMLSelectElement::indexOfSelectedOption() const
 {
-    return optionToListIndex(selectedIndex());
+    return selectedListIndex();
 }

 int HTMLSelectElement::optionCount() const

--- a/third_party/WebKit/Source/core/html/HTMLSelectElement.h
+++ b/third_party/WebKit/Source/core/html/HTMLSelectElement.h
@@ -55,6 +55,8 @@ public:

    int selectedIndex() const;
    void setSelectedIndex(int);
+    // `listIndex' version of |selectedIndex|.
+    int selectedListIndex() const;

    // For ValidityState
    String validationMessage() const override;

--- a/third_party/WebKit/Source/web/ExternalPopupMenu.cpp
+++ b/third_party/WebKit/Source/web/ExternalPopupMenu.cpp
@@ -264,7 +264,7 @@ void ExternalPopupMenu::getPopupMenuInfo(WebPopupMenuInfo& info, HTMLSelectEleme
    const ComputedStyle& menuStyle = ownerElement.computedStyle() ? *ownerElement.computedStyle() : *ownerElement.ensureComputedStyle();
    info.itemHeight = menuStyle.font().getFontMetrics().height();
    info.itemFontSize = static_cast<int>(menuStyle.font().getFontDescription().computedSize());
-    info.selectedIndex = toExternalPopupMenuItemIndex(ownerElement.optionToListIndex(ownerElement.selectedIndex()), ownerElement);
+    info.selectedIndex = toExternalPopupMenuItemIndex(ownerElement.selectedListIndex(), ownerElement);
    info.rightAligned = menuStyle.direction() == RTL;
    info.allowMultipleSelection = ownerElement.multiple();
    if (count < itemCount)

--- a/third_party/WebKit/Source/web/PopupMenuImpl.cpp
+++ b/third_party/WebKit/Source/web/PopupMenuImpl.cpp
@@ -253,7 +253,7 @@ void PopupMenuImpl::writeDocument(SharedBuffer* data)
    data->append(Platform::current()->loadResource("listPicker.css"));
    PagePopupClient::addString("</style></head><body><div id=main>Loading...</div><script>\n"
        "window.dialogArguments = {\n", data);
-    addProperty("selectedIndex", ownerElement.optionToListIndex(ownerElement.selectedIndex()), data);
+    addProperty("selectedIndex", ownerElement.selectedListIndex(), data);
    const ComputedStyle* ownerStyle = ownerElement.computedStyle();
    ItemIterationContext context(*ownerStyle, data);
    context.serializeBaseStyle();