cc: Start using raster/eviction iterators in tile manager

cc/layers/picture_layer_impl.h

Index: cc/layers/picture_layer_impl.h
diff --git a/cc/layers/picture_layer_impl.h b/cc/layers/picture_layer_impl.h
index afd96aa97dfd30467de5beb6f259b39ab928ec91..5865ec4a6607425e18882e8119ce8e48d79f3798 100644
--- a/cc/layers/picture_layer_impl.h
+++ b/cc/layers/picture_layer_impl.h
@@ -38,6 +38,8 @@ class CC_EXPORT PictureLayerImpl
     LayerRasterTileIterator& operator++();
     operator bool() const;
 
+    bool HasTilesRequiredForActivation() const;
+
    private:
     enum IteratorType { LOW_RES, HIGH_RES, NUM_ITERATORS };
 
@@ -136,6 +138,9 @@ class CC_EXPORT PictureLayerImpl
   PictureLayerImpl* GetTwinLayer() { return twin_layer_; }
   WhichTree GetTree() const;
   bool IsOnActiveOrPendingTree() const;
+  bool LayerRegisteredInTileManager() const {
+    return !layer_needs_to_register_itself_;
+  }
 
  protected:
   friend class LayerRasterTileIterator;