Fix 9patch rendering in ExpandableListView.

Change-Id: I60843d61a40b0cb7dd09923cb4489a5a76f20486
diff --git a/libs/hwui/Debug.h b/libs/hwui/Debug.h
index bdd8e73..71ec760 100644
--- a/libs/hwui/Debug.h
+++ b/libs/hwui/Debug.h
@@ -37,6 +37,10 @@
 // Turn on to display vertex and tex coords data about 9patch objects
 // This flag requires DEBUG_PATCHES to be turned on
 #define DEBUG_PATCHES_VERTICES 0
+// Turn on to display vertex and tex coords data used by empty quads
+// in 9patch objects
+// This flag requires DEBUG_PATCHES to be turned on
+#define DEBUG_PATCHES_EMPTY_VERTICES 0
 
 // Turn on to display debug info about paths
 #define DEBUG_PATHS 0