Cancel layer update when a layer is about to be destroyed
Bug #9310706

Change-Id: I73eea6314c326f15a979617e3a05b525935f0d3f
diff --git a/libs/hwui/Layer.cpp b/libs/hwui/Layer.cpp
index 7c22bbb..f409d3e 100644
--- a/libs/hwui/Layer.cpp
+++ b/libs/hwui/Layer.cpp
@@ -213,6 +213,16 @@
     deferredUpdateScheduled = false;
 }
 
+void Layer::cancelDefer() {
+    renderer = NULL;
+    displayList = NULL;
+    deferredUpdateScheduled = false;
+    if (deferredList) {
+        delete deferredList;
+        deferredList = NULL;
+    }
+}
+
 void Layer::flush() {
     if (deferredList) {
         renderer->setViewport(layer.getWidth(), layer.getHeight());