Bug 470711 - Newly modernized tabs look cut off if the last one is hidden, r=josh r+sr=roc

widget/src/xpwidgets/nsNativeTheme.cpp

@@ -264,7 +264,13 @@ nsNativeTheme::IsFirstTab(nsIFrame* aFrame)
   if (!aFrame)
     return PR_FALSE;
 
-  return aFrame->GetContent()->HasAttr(kNameSpaceID_None, nsWidgetAtoms::firsttab);
+  nsIFrame* first = aFrame->GetParent()->GetFirstChild(nsnull);
+  while (first) {
+    if (first->GetRect().width > 0 && first->GetContent()->Tag() == nsWidgetAtoms::tab)
+      return (first == aFrame);
+    first = first->GetNextSibling();
+  }
+  return PR_FALSE;
 }
 
 PRBool
@@ -273,7 +279,11 @@ nsNativeTheme::IsLastTab(nsIFrame* aFrame)
   if (!aFrame)
     return PR_FALSE;
 
-  return aFrame->GetContent()->HasAttr(kNameSpaceID_None, nsWidgetAtoms::lasttab);
+  while ((aFrame = aFrame->GetNextSibling())) {
+    if (aFrame->GetRect().width > 0 && aFrame->GetContent()->Tag() == nsWidgetAtoms::tab)
+      return PR_FALSE;
+  }
+  return PR_TRUE;
 }
 
 PRBool

widget/src/xpwidgets/nsWidgetAtomList.h

@@ -119,6 +119,7 @@ WIDGET_ATOM(state, "state")
 WIDGET_ATOM(step, "step")
 WIDGET_ATOM(Stop, "Stop")
 WIDGET_ATOM(_true, "true")
+WIDGET_ATOM(tab, "tab")
 WIDGET_ATOM(tree, "tree")
 WIDGET_ATOM(treecolpicker, "treecolpicker")
 WIDGET_ATOM(type, "type")