Backed out changeset aaaf793a4dd0 (bug 1344839) for permafailing test_leaf_layers_partition_browser_window.xul on Windows 8 x64 debug. r=backout

widget/gtk/nsWindow.cpp

@@ -4303,12 +4303,6 @@ nsWindow::SetTransparencyMode(nsTransparencyMode aMode)
         topWindow->SetTransparencyMode(aMode);
         return;
     }
-
-    if (mWindowType != eWindowType_popup) {
-        NS_WARNING("Cannot set transparency mode on non-popup windows.");
-        return;
-    }
-
     bool isTransparent = aMode == eTransparencyTransparent;
 
     if (mIsTransparent == isTransparent)