Update <select> when any of its <option> children has "display: none"

Source/core/html/HTMLSelectElement.cpp

Index: Source/core/html/HTMLSelectElement.cpp
diff --git a/Source/core/html/HTMLSelectElement.cpp b/Source/core/html/HTMLSelectElement.cpp
index ed9942c1b431faf10bf5242adf2dab270549dd4b..4c08b470faea4f74108878d90be47ade54cbd2e3 100644
--- a/Source/core/html/HTMLSelectElement.cpp
+++ b/Source/core/html/HTMLSelectElement.cpp
@@ -74,6 +74,7 @@ HTMLSelectElement::HTMLSelectElement(Document& document, HTMLFormElement* form)
     , m_activeSelectionState(false)
     , m_shouldRecalcListItems(false)
     , m_suggestedIndex(-1)
+    , m_optionChildChangedTimer(this, &HTMLSelectElement::timerFired)
 {
     ScriptWrappable::init(this);
 }
@@ -508,11 +509,12 @@ int HTMLSelectElement::nextValidIndex(int listIndex, SkipDirection direction, in
     int size = listItems.size();
     for (listIndex += direction; listIndex >= 0 && listIndex < size; listIndex += direction) {
         --skip;
-        if (!listItems[listIndex]->isDisabledFormControl() && isHTMLOptionElement(*listItems[listIndex])) {
-            lastGoodIndex = listIndex;
-            if (skip <= 0)
-                break;
-        }
+        HTMLElement* element = listItems[listIndex];
+        if (!isHTMLOptionElement(*element) || toHTMLOptionElement(element)->isDisabledFormControl() || !toHTMLOptionElement(element)->isDisplayNone())
+            continue;
+        lastGoodIndex = listIndex;
+        if (skip <= 0)
+            break;
     }
     return lastGoodIndex;
 }
@@ -625,7 +627,7 @@ void HTMLSelectElement::updateListBoxSelection(bool deselectOtherOptions)
     const Vector<HTMLElement*>& items = listItems();
     for (unsigned i = 0; i < items.size(); ++i) {
         HTMLElement* element = items[i];
-        if (!isHTMLOptionElement(*element) || toHTMLOptionElement(element)->isDisabledFormControl())
+        if (!isHTMLOptionElement(*element) || toHTMLOptionElement(element)->isDisabledFormControl() || !toHTMLOptionElement(element)->isDisplayNone())
             continue;
 
         if (i >= start && i <= end)
@@ -1624,4 +1626,20 @@ bool HTMLSelectElement::supportsAutofocus() const
     return true;
 }
 
+void HTMLSelectElement::updateListOnRenderer()
+{
+    if (m_optionChildChangedTimer.isActive())
+        return;
+    ASSERT(!m_optionChildChangedTimer.isActive());
+    m_optionChildChangedTimer.startOneShot(0, FROM_HERE);

[esprehn, 2014/03/20 17:09:25]

This is not correct, you can't use a timer.

[spartha, 2014/03/21 21:37:36]

Just curious, when is it recommended to use a timer?  

+}
+
+void HTMLSelectElement::timerFired(Timer<HTMLSelectElement>* )
+{
+    setOptionsChangedOnRenderer();
+    // Update the renderer with the new list.
+    if (RenderObject* renderer = this->renderer())
+        renderer->updateFromElement();
+}
+
 } // namespace