more surfaceflinger cleanups

get rid of the "fake rtti" code, and use polymorphism instead.
also simplify how we log SF's state (using polymorphism)

Change-Id: I2bae7c98de4dd207a3e2b00083fa3fde7c467922
diff --git a/libs/surfaceflinger/LayerDim.h b/libs/surfaceflinger/LayerDim.h
index d4672a1..19a9990 100644
--- a/libs/surfaceflinger/LayerDim.h
+++ b/libs/surfaceflinger/LayerDim.h
@@ -37,11 +37,6 @@
     static int32_t sWidth;
     static int32_t sHeight;
 public:    
-    static const uint32_t typeInfo;
-    static const char* const typeID;
-    virtual char const* getTypeID() const { return typeID; }
-    virtual uint32_t getTypeInfo() const { return typeInfo; }
-    
                 LayerDim(SurfaceFlinger* flinger, DisplayID display,
                         const sp<Client>& client, int32_t i);
         virtual ~LayerDim();
@@ -49,6 +44,7 @@
     virtual void onDraw(const Region& clip) const;
     virtual bool needsBlending() const  { return true; }
     virtual bool isSecure() const       { return false; }
+    virtual const char* getTypeId() const { return "LayerDim"; }
 
     static void initDimmer(SurfaceFlinger* flinger, uint32_t w, uint32_t h);
 };