diff -r b5c41404f2d1 -r bb03098c4dde src/hotspot/share/gc/g1/g1Policy.hpp
--- a/src/hotspot/share/gc/g1/g1Policy.hpp	Fri Dec 21 18:26:55 2018 +0000
+++ b/src/hotspot/share/gc/g1/g1Policy.hpp	Fri Dec 21 08:18:59 2018 -0800
@@ -25,6 +25,7 @@
 #ifndef SHARE_VM_GC_G1_G1POLICY_HPP
 #define SHARE_VM_GC_G1_G1POLICY_HPP
 
+#include "gc/g1/g1CollectorPolicy.hpp"
 #include "gc/g1/g1CollectorState.hpp"
 #include "gc/g1/g1GCPhaseTimes.hpp"
 #include "gc/g1/g1InCSetState.hpp"
@@ -91,7 +92,7 @@
   // for the first time during initialization.
   uint   _reserve_regions;
 
-  G1YoungGenSizer _young_gen_sizer;
+  G1YoungGenSizer* _young_gen_sizer;
 
   uint _free_regions_at_end_of_collection;
 
@@ -282,10 +283,12 @@
   void abort_time_to_mixed_tracking();
 public:
 
-  G1Policy(STWGCTimer* gc_timer);
+  G1Policy(G1CollectorPolicy* policy, STWGCTimer* gc_timer);
 
   virtual ~G1Policy();
 
+  static G1Policy* create_policy(G1CollectorPolicy* policy, STWGCTimer* gc_timer_stw);
+
   G1CollectorState* collector_state() const;
 
   G1GCPhaseTimes* phase_times() const { return _phase_times; }
@@ -298,7 +301,7 @@
   // This should be called after the heap is resized.
   void record_new_heap_size(uint new_number_of_regions);
 
-  void init(G1CollectedHeap* g1h, G1CollectionSet* collection_set);
+  virtual void init(G1CollectedHeap* g1h, G1CollectionSet* collection_set);
 
   void note_gc_start();
 
@@ -308,11 +311,11 @@
 
   // Record the start and end of an evacuation pause.
   void record_collection_pause_start(double start_time_sec);
-  void record_collection_pause_end(double pause_time_ms, size_t cards_scanned, size_t heap_used_bytes_before_gc);
+  virtual void record_collection_pause_end(double pause_time_ms, size_t cards_scanned, size_t heap_used_bytes_before_gc);
 
   // Record the start and end of a full collection.
   void record_full_collection_start();
-  void record_full_collection_end();
+  virtual void record_full_collection_end();
 
   // Must currently be called while the world is stopped.
   void record_concurrent_mark_init_end(double mark_init_elapsed_time_ms);
@@ -432,6 +435,10 @@
   void update_max_gc_locker_expansion();
 
   void update_survivors_policy();
+
+  virtual bool force_upgrade_to_full() {
+    return false;
+  }
 };
 
 #endif // SHARE_VM_GC_G1_G1POLICY_HPP