fix a memory corruption where a SF Client could be used after it's been destroyed
diff --git a/libs/surfaceflinger/LayerDim.h b/libs/surfaceflinger/LayerDim.h
index d9b70b4..33bd49d 100644
--- a/libs/surfaceflinger/LayerDim.h
+++ b/libs/surfaceflinger/LayerDim.h
@@ -44,7 +44,7 @@
     virtual uint32_t getTypeInfo() const { return typeInfo; }
     
                 LayerDim(SurfaceFlinger* flinger, DisplayID display,
-                        Client* client, int32_t i);
+                        const sp<Client>& client, int32_t i);
         virtual ~LayerDim();
 
     virtual void onDraw(const Region& clip) const;