Widget::ShouldUseNativeFrame is now meaningful on Linux.

chrome/browser/ui/views/tabs/tab.cc

Index: chrome/browser/ui/views/tabs/tab.cc
diff --git a/chrome/browser/ui/views/tabs/tab.cc b/chrome/browser/ui/views/tabs/tab.cc
index fa9e9d88a2bf886462a3959999e8debd57b0c552..9046efad9035338e22310b4c8fcfb21662805255 100644
--- a/chrome/browser/ui/views/tabs/tab.cc
+++ b/chrome/browser/ui/views/tabs/tab.cc
@@ -1608,6 +1608,13 @@ bool Tab::ShouldShowCloseBox() const {
       IconCapacity(), data().mini, IsActive());
 }
 
+bool Tab::UsingWindowsGlass(const views::Widget* widget) const {
+#if defined(OS_WIN)
+  return widget && widget->GetTopLevelWidget()->ShouldUseNativeFrame();
+#endif
+return false;
+}
+
 double Tab::GetThrobValue() {
   bool is_selected = IsSelected();
   double min = is_selected ? kSelectedTabOpacity : 0;
@@ -1686,7 +1693,7 @@ gfx::Rect Tab::GetImmersiveBarRect() const {
 void Tab::GetTabIdAndFrameId(views::Widget* widget,
                              int* tab_id,
                              int* frame_id) const {
-  if (widget && widget->GetTopLevelWidget()->ShouldUseNativeFrame()) {
+  if (UsingWindowsGlass(widget)) {
     *tab_id = IDR_THEME_TAB_BACKGROUND_V;
     *frame_id = 0;
   } else if (data().incognito) {