8236073: G1: Use SoftMaxHeapSize to guide GC heuristics

@@ -55,9 +55,12 @@
   virtual size_t expansion_amount();
 
   // Clear ratio tracking data used by expansion_amount().
   void clear_ratio_check_data();
 
+  // Check if heap size can be shrinked
+  bool can_shrink_heap_size_to(size_t heap_size);
+
   static G1HeapSizingPolicy* create(const G1CollectedHeap* g1h, const G1Analytics* analytics);
 };
 
 #endif // SHARE_GC_G1_G1HEAPSIZINGPOLICY_HPP