cc: Remove tile sharing from tilings.

cc/resources/tiling_set_raster_queue_all.h

Index: cc/resources/tiling_set_raster_queue_all.h
diff --git a/cc/resources/tiling_set_raster_queue_all.h b/cc/resources/tiling_set_raster_queue_all.h
index ebca838f232b288c00e6e6770d3d97e997d23bf2..f497afdad92a7e111916e7ede189666076785c11 100644
--- a/cc/resources/tiling_set_raster_queue_all.h
+++ b/cc/resources/tiling_set_raster_queue_all.h
@@ -64,6 +64,18 @@ class CC_EXPORT TilingSetRasterQueueAll {
     TilingData::Iterator iterator_;
   };
 
+  class PendingVisibleTilingIterator : public OnePriorityRectIterator {
+   public:
+    PendingVisibleTilingIterator() = default;
+    PendingVisibleTilingIterator(PictureLayerTiling* tiling,
+                                 TilingData* tiling_data);
+
+    PendingVisibleTilingIterator& operator++();
+
+   private:
+    TilingData::DifferenceIterator iterator_;
+  };
+
   // Iterates over skewport only, spiral around the visible rect.
   class SkewportTilingIterator : public OnePriorityRectIterator {
    public:
@@ -74,6 +86,7 @@ class CC_EXPORT TilingSetRasterQueueAll {
 
    private:
     TilingData::SpiralDifferenceIterator iterator_;
+    gfx::Rect pending_visible_rect_;
   };
 
   // Iterates over soon border only, spiral around the visible rect.
@@ -87,6 +100,7 @@ class CC_EXPORT TilingSetRasterQueueAll {
 
    private:
     TilingData::SpiralDifferenceIterator iterator_;
+    gfx::Rect pending_visible_rect_;
   };
 
   // Iterates over eventually rect only, spiral around the soon rect.
@@ -100,6 +114,7 @@ class CC_EXPORT TilingSetRasterQueueAll {
 
    private:
     TilingData::SpiralDifferenceIterator iterator_;
+    gfx::Rect pending_visible_rect_;
   };
 
   // Iterates over all of the above phases in the following order: visible,
@@ -109,7 +124,7 @@ class CC_EXPORT TilingSetRasterQueueAll {
     TilingIterator();
     explicit TilingIterator(PictureLayerTiling* tiling,
                             TilingData* tiling_data);
-    ~TilingIterator() = default;
+    ~TilingIterator();
 
     bool done() const { return current_tile_ == nullptr; }
     const Tile* operator*() const { return current_tile_; }
@@ -118,6 +133,7 @@ class CC_EXPORT TilingSetRasterQueueAll {
       switch (phase_) {
         case VISIBLE_RECT:
           return TilePriority::NOW;
+        case PENDING_VISIBLE_RECT:
         case SKEWPORT_RECT:
         case SOON_BORDER_RECT:
           return TilePriority::SOON;
@@ -131,8 +147,14 @@ class CC_EXPORT TilingSetRasterQueueAll {
     TilingIterator& operator++();
 
    private:
+    // PENDING VISIBLE RECT refers to the visible rect that will become current
+    // upon activation (ie, the pending tree's visible rect). Tiles in this
+    // region that are not part of the current visible rect are all handled
+    // here. Note that when processing a pending tree, this rect is the same as
+    // the visible rect so no tiles are processed in this case.
     enum Phase {
       VISIBLE_RECT,
+      PENDING_VISIBLE_RECT,
       SKEWPORT_RECT,
       SOON_BORDER_RECT,
       EVENTUALLY_RECT
@@ -147,26 +169,32 @@ class CC_EXPORT TilingSetRasterQueueAll {
 
     Tile* current_tile_;
     VisibleTilingIterator visible_iterator_;
+    PendingVisibleTilingIterator pending_visible_iterator_;
     SkewportTilingIterator skewport_iterator_;
     SoonBorderTilingIterator soon_border_iterator_;
     EventuallyTilingIterator eventually_iterator_;
   };
 
-  enum IteratorType { LOW_RES, HIGH_RES, NUM_ITERATORS };
+  enum IteratorType {
+    LOW_RES,
+    HIGH_RES,
+    ACTIVE_NON_IDEAL_PENDING_HIGH_RES,
+    NUM_ITERATORS
+  };
 
   void AdvanceToNextStage();
 
   PictureLayerTilingSet* tiling_set_;
 
   struct IterationStage {
+    IterationStage(IteratorType type, TilePriority::PriorityBin bin);
     IteratorType iterator_type;
     TilePriority::PriorityBin tile_type;
   };
 
   size_t current_stage_;
 
-  // One low res stage, and three high res stages.
-  IterationStage stages_[4];
+  std::vector<IterationStage> stages_;
   TilingIterator iterators_[NUM_ITERATORS];
 };