Bug 553814, don't set listbox minheight, which prevents the scrollbar from appearing when the rows attribute is used, r=neil

layout/xul/base/src/nsListBoxBodyFrame.cpp

@@ -261,21 +261,8 @@ nsListBoxBodyFrame::AttributeChanged(PRInt32 aNameSpaceID,
   nsresult rv = NS_OK;
 
   if (aAttribute == nsGkAtoms::rows) {
-    nsAutoString rows;
-    mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::rows, rows);
-    
-    if (!rows.IsEmpty()) {
-      PRInt32 dummy;
-      PRInt32 count = rows.ToInteger(&dummy);
-      PRInt32 rowHeight = GetRowHeightAppUnits();
-      rowHeight = nsPresContext::AppUnitsToIntCSSPixels(rowHeight);
-      nsAutoString value;
-      value.AppendInt(rowHeight*count);
-      mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::minheight, value, PR_FALSE);
-
-      PresContext()->PresShell()->
-        FrameNeedsReflow(this, nsIPresShell::eStyleChange, NS_FRAME_IS_DIRTY);
-    }
+    PresContext()->PresShell()->
+      FrameNeedsReflow(this, nsIPresShell::eStyleChange, NS_FRAME_IS_DIRTY);
   }
   else
     rv = nsBoxFrame::AttributeChanged(aNameSpaceID, aAttribute, aModType);
@@ -660,20 +647,6 @@ nsListBoxBodyFrame::SetRowHeight(nscoord aRowHeight)
 { 
   if (aRowHeight > mRowHeight) { 
     mRowHeight = aRowHeight;
-    
-    nsAutoString rows;
-    mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::rows, rows);
-    if (rows.IsEmpty())
-      mContent->GetAttr(kNameSpaceID_None, nsGkAtoms::size, rows);
-    
-    if (!rows.IsEmpty()) {
-      PRInt32 dummy;
-      PRInt32 count = rows.ToInteger(&dummy);
-      PRInt32 rowHeight = nsPresContext::AppUnitsToIntCSSPixels(aRowHeight);
-      nsAutoString value;
-      value.AppendInt(rowHeight*count);
-      mContent->SetAttr(kNameSpaceID_None, nsGkAtoms::minheight, value, PR_FALSE);
-    }
 
     // signal we need to dirty everything 
     // and we want to be notified after reflow

toolkit/content/tests/widgets/test_hiddenpaging.xul

@@ -97,6 +97,13 @@ function testListbox()
 {
   var id = "listbox";
   var listbox = document.getElementById(id);
+
+  // Check that a scrollbar is visible by comparing the width of the listitem
+  // with the width of the listbox. This is a simple way to do this without
+  // checking the anonymous content.
+  ok(listbox.firstChild.getBoundingClientRect().width < listbox.getBoundingClientRect().width - 10,
+     id + ": Scrollbar visible");
+
   listbox.selectedIndex = 0;
   sendKey("PAGE_DOWN", id);
   is(listbox.selectedItem.id, id + "_item8", id + ": Page down should go to the item one visible page away");