cc: Do not ignore layers without valid priorities during eviction.

cc/layers/picture_layer_impl.cc

Index: cc/layers/picture_layer_impl.cc
diff --git a/cc/layers/picture_layer_impl.cc b/cc/layers/picture_layer_impl.cc
index c3c7ca021104ba5f2468b233838d45beee16c845..066421951ff33cd849e5a00d068522fd625edf31 100644
--- a/cc/layers/picture_layer_impl.cc
+++ b/cc/layers/picture_layer_impl.cc
@@ -1585,9 +1585,13 @@ PictureLayerImpl::LayerEvictionTileIterator::LayerEvictionTileIterator()
 
 PictureLayerImpl::LayerEvictionTileIterator::LayerEvictionTileIterator(
     PictureLayerImpl* layer,
+    const PictureLayerImpl* twin_layer,

[vmpstr, 2014/10/31 15:35:49]

layer itself has access to the twin, let's just get it there so that we don't
have to pass extra parameters.

[USE eero AT chromium.org, 2014/11/04 17:47:57]

Done.

     TreePriority tree_priority)
     : layer_(layer),
       tree_priority_(tree_priority),
+      use_tile_priority_rects_(layer->HasValidTilePriorities()),
+      use_twin_tile_priority_rects_(twin_layer &&
+                                    twin_layer->HasValidTilePriorities()),
       current_category_(PictureLayerTiling::EVENTUALLY),
       current_tiling_range_type_(PictureLayerTilingSet::HIGHER_THAN_HIGH_RES),
       current_tiling_(CurrentTilingRange().start - 1u) {
@@ -1602,7 +1606,9 @@ PictureLayerImpl::LayerEvictionTileIterator::LayerEvictionTileIterator(
     current_iterator_ = PictureLayerTiling::TilingEvictionTileIterator(
         layer_->tilings_->tiling_at(CurrentTilingIndex()),
         tree_priority,
-        current_category_);
+        current_category_,
+        use_tile_priority_rects_,
+        use_twin_tile_priority_rects_);
   } while (!current_iterator_);
 }
 
@@ -1631,7 +1637,9 @@ operator++() {
     current_iterator_ = PictureLayerTiling::TilingEvictionTileIterator(
         layer_->tilings_->tiling_at(CurrentTilingIndex()),
         tree_priority_,
-        current_category_);
+        current_category_,
+        use_tile_priority_rects_,
+        use_twin_tile_priority_rects_);
   }
   return *this;
 }