Took out eMetric_SubmenuDelay by mistake, this re-adds it back in.

This was for Photon UI only
r=kedl

widget/src/photon/nsLookAndFeel.cpp

@@ -168,6 +168,9 @@ NS_IMETHODIMP nsLookAndFeel::GetMetric(const nsMetricID aID, PRInt32 & aMetric)
 	case eMetric_CaretWidthTwips:
     aMetric = 20;
     break;
+  case eMetric_SubmenuDelay:
+    aMetric = 200;
+    break;
   default:
     aMetric = -1;
     res = NS_ERROR_FAILURE;