cc: Move tiling management out of draw properties calculation.

cc/resources/picture_layer_tiling_set.cc

Index: cc/resources/picture_layer_tiling_set.cc
diff --git a/cc/resources/picture_layer_tiling_set.cc b/cc/resources/picture_layer_tiling_set.cc
index d292d83fab2a53d05ba39d7ca579e3db11c2c0cc..267ee08ef4818fc44b56dd47fc58e9f8293f358b 100644
--- a/cc/resources/picture_layer_tiling_set.cc
+++ b/cc/resources/picture_layer_tiling_set.cc
@@ -324,10 +324,17 @@ void PictureLayerTilingSet::UpdateTilePriorities(
   gfx::Rect visible_layer_rect = gfx::ScaleToEnclosingRect(
       visible_content_rect, 1.f / layer_contents_scale);
 
+  float max_layer_contents_scale = layer_contents_scale;

[enne (OOO), 2014/05/28 18:42:20]

You should not need this.  The scale used to be max but is now 1, but this math
should all still work out using that scale.

What is failing, specifically?

[sohanjg, 2014/05/29 13:07:04]

In LayerEvictionTileIterator test, tile->required_for_activation() check fails
for some tiles.
The problem is the PictureLayerImplTest.LayerEvictionTileIterator iterates over
the tiles in a wrong order, the order is again decided the way we pushed the
tiles in the iterator(based on priority), which seems to be different now.
The only reason i found is that previously in
PictureLayerTiling::UpdateTilePriorities the scaling was different than now and
based on that TilePriorities may have been assigned.

Please suggest if there can be any alternate way.

+  for (size_t i = 0; i < this->num_tilings(); ++i) {
+    const PictureLayerTiling* tiling = this->tiling_at(i);
+    max_layer_contents_scale =
+        std::max(max_layer_contents_scale, tiling->contents_scale());
+  }
+
   for (size_t i = 0; i < tilings_.size(); ++i) {
     tilings_[i]->UpdateTilePriorities(tree,
                                       visible_layer_rect,
-                                      layer_contents_scale,
+                                      max_layer_contents_scale,
                                       current_frame_time_in_seconds);
   }
 }