8236073: G1: Use SoftMaxHeapSize to guide GC heuristics

*** 146,155 ****
--- 146,156 ----
    double _cur_derived_pointer_table_update_time_ms;
  
    double _cur_clear_ct_time_ms;
    double _cur_expand_heap_time_ms;
    double _cur_ref_proc_time_ms;
+   double _cur_adjust_heap_time_ms;
  
    double _cur_collection_start_sec;
    double _root_region_scan_wait_time_ms;
  
    double _external_accounted_time_ms;
*** 262,271 ****
--- 263,276 ----
  
    void record_expand_heap_time(double ms) {
      _cur_expand_heap_time_ms = ms;
    }
  
+   void record_or_add_adjust_heap_time(double ms) {
+     _cur_adjust_heap_time_ms += ms;
+   }
+ 
    void record_initial_evac_time(double ms) {
      _cur_collection_initial_evac_time_ms = ms;
    }
  
    void record_or_add_optional_evac_time(double ms) {
*** 401,410 ****
--- 406,419 ----
  
    double cur_expand_heap_time_ms() {
      return _cur_expand_heap_time_ms;
    }
  
+   double cur_adjust_heap_time_ms() {
+     return _cur_adjust_heap_time_ms;
+   }
+ 
    double root_region_scan_wait_time_ms() {
      return _root_region_scan_wait_time_ms;
    }
  
    double young_cset_choice_time_ms() {