Consider occluded tiles during eviction with occluded as Tile property.

cc/resources/tile_priority.h

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef CC_RESOURCES_TILE_PRIORITY_H_
 #define CC_RESOURCES_TILE_PRIORITY_H_
 
 #include <algorithm>
 #include <limits>
 
@@ skipping 116 matching lines @@
 
   // NOTE: Be sure to update TreePriorityAsValue and kBinPolicyMap when adding
   // or reordering fields.
 };
 scoped_ptr<base::Value> TileMemoryLimitPolicyAsValue(
     TileMemoryLimitPolicy policy);
 
 enum TreePriority {
   SAME_PRIORITY_FOR_BOTH_TREES,
   SMOOTHNESS_TAKES_PRIORITY,
-  NEW_CONTENT_TAKES_PRIORITY
-
+  NEW_CONTENT_TAKES_PRIORITY,
+  NUM_TREE_PRIORITIES
   // Be sure to update TreePriorityAsValue when adding new fields.
 };
 scoped_ptr<base::Value> TreePriorityAsValue(TreePriority prio);
 
 class GlobalStateThatImpactsTilePriority {
  public:
   GlobalStateThatImpactsTilePriority()
       : memory_limit_policy(ALLOW_NOTHING),
         soft_memory_limit_in_bytes(0),
         hard_memory_limit_in_bytes(0),
@@ skipping 18 matching lines @@
   bool operator!=(const GlobalStateThatImpactsTilePriority& other) const {
     return !(*this == other);
   }
 
   scoped_ptr<base::Value> AsValue() const;
 };
 
 }  // namespace cc
 
 #endif  // CC_RESOURCES_TILE_PRIORITY_H_