Revert of Introducing the LLVM greedy register allocator.

src/zone-containers.h

 // Copyright 2014 the V8 project 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 V8_ZONE_CONTAINERS_H_
 #define V8_ZONE_CONTAINERS_H_
 
 #include <deque>
 #include <list>
 #include <map>
@@ skipping 45 matching lines @@
 // own home-grown ZoneList that actually is a ZoneVector.
 template <typename T>
 class ZoneLinkedList : public std::list<T, zone_allocator<T>> {
  public:
   // Constructs an empty list.
   explicit ZoneLinkedList(Zone* zone)
       : std::list<T, zone_allocator<T>>(zone_allocator<T>(zone)) {}
 };
 
 
-// A wrapper subclass std::priority_queue to make it easy to construct one
-// that uses a zone allocator.
-template <typename T, typename Compare = std::less<T>>
-class ZonePriorityQueue : public std::priority_queue<T, ZoneVector<T>> {
- public:
-  // Constructs an empty list.
-  explicit ZonePriorityQueue(Zone* zone)
-      : std::priority_queue<T, ZoneVector<T>>(Compare(), ZoneVector<T>(zone)) {}
-};
-
-
 // A wrapper subclass for std::queue to make it easy to construct one
 // that uses a zone allocator.
 template <typename T>
 class ZoneQueue : public std::queue<T, ZoneDeque<T>> {
  public:
   // Constructs an empty queue.
   explicit ZoneQueue(Zone* zone)
       : std::queue<T, ZoneDeque<T>>(ZoneDeque<T>(zone)) {}
 };
 
@@ skipping 35 matching lines @@
 
 
 // Typedefs to shorten commonly used vectors.
 typedef ZoneVector<bool> BoolVector;
 typedef ZoneVector<int> IntVector;
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_ZONE_CONTAINERS_H_