cc: Remove vectors from tiling eviction tile iterator.

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 d49205137510bd9d5f3bc57e89a785d42de65616..2f1814b2aadbb24bfd7ded2db3aeee4f392f16ca 100644
--- a/cc/layers/picture_layer_impl.h
+++ b/cc/layers/picture_layer_impl.h
@@ -77,14 +77,33 @@ class CC_EXPORT PictureLayerImpl
     operator bool() const;
 
    private:
+    enum RangeType {
+      HIGHER_THAN_HIGH_RES,
+      LOWER_THAN_LOW_RES,
+      BETWEEN_HIGH_AND_LOW_RES,
+      LOW_RES,
+      HIGH_RES,
+      NUM_RANGE_TYPES
+    };
+    struct TilingIterationRange {
+      int start_index;
+      int one_past_end_index;
+    };
+
+    void ConstructRanges();
+    bool CurrentTilingIndexInRange();
     void AdvanceToNextIterator();
-    bool IsCorrectType(
-        PictureLayerTiling::TilingEvictionTileIterator* it) const;
+    bool AdvanceTiling();
+    bool AdvanceRange();
+    bool AdvanceStage();
 
-    std::vector<PictureLayerTiling::TilingEvictionTileIterator> iterators_;
-    size_t iterator_index_;
+    PictureLayerTiling::TilingEvictionTileIterator iterator_;
+    int tiling_index_;

[reveman, 2014/07/29 21:41:33]

nit: current_tiling_

btw, might be cleaner to maintain this as an offset in the tiling range rather
than offset from first tiling in the tiling set

[vmpstr, 2014/07/30 00:18:52]

I changed it to current_tiling_index_. I would prefer to keep the word "index"
in there, so it's clear that this is not an actual tiling object/pointer.

[reveman, 2014/07/30 16:06:48]

Acknowledged.

     TilePriority::PriorityBin iteration_stage_;

[reveman, 2014/07/29 21:41:33]

Maybe add something like this to make it clear that required_for_activation is
part of the stage.

struct IterationStage {
  bool required_for_activation;
  TilePriority::PriorityBin tile_type;
};

IterationStage current_stage_;

[vmpstr, 2014/07/30 00:18:52]

Done.

+    TilingIterationRange ranges_[NUM_RANGE_TYPES];
+    int range_index_;

[reveman, 2014/07/29 21:41:33]

nit: current_range_

and "TilingSet::TilingRangeType current_range_" when rebased on my patch.

[vmpstr, 2014/07/30 00:18:52]

Likewise I changed it to current_range_type_

[reveman, 2014/07/30 16:06:48]

Acknowledged.

     bool required_for_activation_;
+    TreePriority tree_priority_;
 
     PictureLayerImpl* layer_;
   };