Bug 619996, part d: use nsHTMLSelectElement::FromContent in nsListControlFrame; r=bz

layout/forms/nsListControlFrame.cpp

@@ -79,7 +79,7 @@
 #ifdef ACCESSIBILITY
 #include "nsAccessibilityService.h"
 #endif
-#include "nsISelectElement.h"
+#include "nsHTMLSelectElement.h"
 #include "nsIPrivateDOMEvent.h"
 #include "nsCSSRendering.h"
 #include "nsITheme.h"
@@ -285,10 +285,8 @@ void nsListControlFrame::PaintFocus(nsIRenderingContext& aRC, nsPoint aPt)
 
   nsCOMPtr<nsIContent> focusedContent;
 
-  nsCOMPtr<nsIDOMHTMLSelectElement> selectDOMElement(do_QueryInterface(mContent));
-  NS_ASSERTION(selectDOMElement, "Can't be null");
-
-  nsCOMPtr<nsISelectElement> selectElement(do_QueryInterface(mContent));
+  nsRefPtr<nsHTMLSelectElement> selectElement =
+    nsHTMLSelectElement::FromContent(mContent);
   NS_ASSERTION(selectElement, "Can't be null");
 
   // If we have a selected index then get that child frame
@@ -299,20 +297,17 @@ void nsListControlFrame::PaintFocus(nsIRenderingContext& aRC, nsPoint aPt)
       childframe = focusedContent->GetPrimaryFrame();
     }
   } else {
-    nsCOMPtr<nsIDOMHTMLSelectElement> selectHTMLElement(do_QueryInterface(mContent));
-    NS_ASSERTION(selectElement, "Can't be null");
-
     // Since there isn't a selected item we need to show a focus ring around the first
     // non-disabled item and skip all the option group elements (nodes)
     nsCOMPtr<nsIDOMNode> node;
 
     PRUint32 length;
-    selectHTMLElement->GetLength(&length);
+    selectElement->GetLength(&length);
     if (length) {
       // find the first non-disabled item
       PRBool isDisabled = PR_TRUE;
-      for (PRInt32 i=0;i<PRInt32(length) && isDisabled;i++) {
-        if (NS_FAILED(selectDOMElement->Item(i, getter_AddRefs(node))) || !node) {
+      for (PRUint32 i = 0; i < length && isDisabled; i++) {
+        if (NS_FAILED(selectElement->Item(i, getter_AddRefs(node))) || !node) {
           break;
         }
         if (NS_FAILED(selectElement->IsOptionDisabled(i, &isDisabled))) {
@@ -1521,7 +1516,8 @@ nsListControlFrame::SetOptionsSelectedFromFrame(PRInt32 aStartIndex,
                                                 PRBool aValue,
                                                 PRBool aClearAll)
 {
-  nsCOMPtr<nsISelectElement> selectElement(do_QueryInterface(mContent));
+  nsRefPtr<nsHTMLSelectElement> selectElement =
+    nsHTMLSelectElement::FromContent(mContent);
   PRBool wasChanged = PR_FALSE;
 #ifdef DEBUG
   nsresult rv = 
@@ -1552,18 +1548,25 @@ nsListControlFrame::ToggleOptionSelectedFromFrame(PRInt32 aIndex)
   }
 
   PRBool value = PR_FALSE;
-  nsresult rv = option->GetSelected(&value);
+#ifdef DEBUG
+  nsresult rv =
+#endif
+    option->GetSelected(&value);
 
   NS_ASSERTION(NS_SUCCEEDED(rv), "GetSelected failed");
-  nsCOMPtr<nsISelectElement> selectElement(do_QueryInterface(mContent));
+  nsRefPtr<nsHTMLSelectElement> selectElement =
+    nsHTMLSelectElement::FromContent(mContent);
   PRBool wasChanged = PR_FALSE;
-  rv = selectElement->SetOptionsSelectedByIndex(aIndex,
-                                                aIndex,
-                                                !value,
-                                                PR_FALSE,
-                                                PR_FALSE,
-                                                PR_TRUE,
-                                                &wasChanged);
+#ifdef DEBUG
+  rv =
+#endif
+    selectElement->SetOptionsSelectedByIndex(aIndex,
+                                             aIndex,
+                                             !value,
+                                             PR_FALSE,
+                                             PR_FALSE,
+                                             PR_TRUE,
+                                             &wasChanged);
 
   NS_ASSERTION(NS_SUCCEEDED(rv), "SetSelected failed");
 
@@ -1845,7 +1848,8 @@ nsListControlFrame::GetHeightOfARow()
 nsresult
 nsListControlFrame::IsOptionDisabled(PRInt32 anIndex, PRBool &aIsDisabled)
 {
-  nsCOMPtr<nsISelectElement> sel(do_QueryInterface(mContent));
+  nsRefPtr<nsHTMLSelectElement> sel =
+    nsHTMLSelectElement::FromContent(mContent);
   if (sel) {
     sel->IsOptionDisabled(anIndex, &aIsDisabled);
     return NS_OK;