cc: Use pointers for heaps in tile manager raster tile priority queue.

cc/resources/raster_tile_priority_queue.cc

Index: cc/resources/raster_tile_priority_queue.cc
diff --git a/cc/resources/raster_tile_priority_queue.cc b/cc/resources/raster_tile_priority_queue.cc
index 3dae625ae3b92349772c93149394986599ee8a2f..d77fc824f5b3d5f1b393d2cba4ed4ba02b00cf34 100644
--- a/cc/resources/raster_tile_priority_queue.cc
+++ b/cc/resources/raster_tile_priority_queue.cc
@@ -14,21 +14,21 @@ class RasterOrderComparator {
       : tree_priority_(tree_priority) {}
 
   bool operator()(
-      const RasterTilePriorityQueue::PairedPictureLayerQueue& a,
-      const RasterTilePriorityQueue::PairedPictureLayerQueue& b) const {
-    if (a.IsEmpty())
+      const RasterTilePriorityQueue::PairedPictureLayerQueue* a,
+      const RasterTilePriorityQueue::PairedPictureLayerQueue* b) const {
+    if (a->IsEmpty())
       return true;
 
-    if (b.IsEmpty())
+    if (b->IsEmpty())
       return false;
 
-    WhichTree a_tree = a.NextTileIteratorTree(tree_priority_);
+    WhichTree a_tree = a->NextTileIteratorTree(tree_priority_);
     const PictureLayerImpl::LayerRasterTileIterator* a_iterator =
-        a_tree == ACTIVE_TREE ? &a.active_iterator : &a.pending_iterator;
+        a_tree == ACTIVE_TREE ? &a->active_iterator : &a->pending_iterator;
 
-    WhichTree b_tree = b.NextTileIteratorTree(tree_priority_);
+    WhichTree b_tree = b->NextTileIteratorTree(tree_priority_);
     const PictureLayerImpl::LayerRasterTileIterator* b_iterator =
-        b_tree == ACTIVE_TREE ? &b.active_iterator : &b.pending_iterator;
+        b_tree == ACTIVE_TREE ? &b->active_iterator : &b->pending_iterator;
 
     const Tile* a_tile = **a_iterator;
     const Tile* b_tile = **b_iterator;
@@ -86,34 +86,39 @@ void RasterTilePriorityQueue::Build(
     paired_queues_.push_back(PairedPictureLayerQueue(*it, tree_priority_));
   }
 
-  std::make_heap(paired_queues_.begin(),
-                 paired_queues_.end(),
+  for (size_t i = 0; i < paired_queues_.size(); ++i) {
+    paired_queues_heap_.push_back(&paired_queues_[i]);
+  }
+
+  std::make_heap(paired_queues_heap_.begin(),
+                 paired_queues_heap_.end(),
                  RasterOrderComparator(tree_priority_));
 }
 
 void RasterTilePriorityQueue::Reset() {
   paired_queues_.clear();
+  paired_queues_heap_.clear();
 }
 
 bool RasterTilePriorityQueue::IsEmpty() const {
-  return paired_queues_.empty() || paired_queues_.front().IsEmpty();
+  return paired_queues_heap_.empty() || paired_queues_heap_.front()->IsEmpty();
 }
 
 Tile* RasterTilePriorityQueue::Top() {
   DCHECK(!IsEmpty());
-  return paired_queues_.front().Top(tree_priority_);
+  return paired_queues_heap_.front()->Top(tree_priority_);
 }
 
 void RasterTilePriorityQueue::Pop() {
   DCHECK(!IsEmpty());
 
-  std::pop_heap(paired_queues_.begin(),
-                paired_queues_.end(),
+  std::pop_heap(paired_queues_heap_.begin(),
+                paired_queues_heap_.end(),
                 RasterOrderComparator(tree_priority_));
-  PairedPictureLayerQueue& paired_queue = paired_queues_.back();
-  paired_queue.Pop(tree_priority_);
-  std::push_heap(paired_queues_.begin(),
-                 paired_queues_.end(),
+  PairedPictureLayerQueue* paired_queue = paired_queues_heap_.back();
+  paired_queue->Pop(tree_priority_);
+  std::push_heap(paired_queues_heap_.begin(),
+                 paired_queues_heap_.end(),
                  RasterOrderComparator(tree_priority_));
 }