cc: Move tiling management out of draw properties calculation.

cc/resources/picture_layer_tiling.cc

Index: cc/resources/picture_layer_tiling.cc
diff --git a/cc/resources/picture_layer_tiling.cc b/cc/resources/picture_layer_tiling.cc
index 9ab2cf5f06b2941c5fb3003c6b154cdcf7fbb962..42a92a8cc6df98b07737cbca82f7403b52a2ca3f 100644
--- a/cc/resources/picture_layer_tiling.cc
+++ b/cc/resources/picture_layer_tiling.cc
@@ -482,7 +482,6 @@ void PictureLayerTiling::UpdateTilePriorities(
     if (find == tiles_.end())
       continue;
     Tile* tile = find->second.get();
-
     tile->SetPriority(tree, now_priority);
   }
 
@@ -530,6 +529,11 @@ void PictureLayerTiling::UpdateTilePriorities(
 
   // Upgrade the priority on border tiles to be SOON.
   current_soon_border_rect_ = visible_rect_in_content_space;
+  float max_tiling_scale = 1.f;
+  for (size_t i = 0; i < this->num_tilings(); ++i) {
+    const PictureLayerTiling* tiling = this->tiling_at(i);
+    max_tiling_scale = std::max(max_tiling_scale, tiling->contents_scale());
+  }
   float border = kSoonBorderDistanceInScreenPixels / content_to_screen_scale;
   current_soon_border_rect_.Inset(-border, -border, -border, -border);
   for (TilingData::DifferenceIterator iter(