Add memory pressure notification API

src/heap/incremental-marking.cc

 // Copyright 2012 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.
 
 #include "src/heap/incremental-marking.h"
 
 #include "src/code-stubs.h"
 #include "src/compilation-cache.h"
 #include "src/conversions.h"
 #include "src/heap/gc-idle-time-handler.h"
@@ skipping 27 matching lines @@
       bytes_scanned_(0),
       allocated_(0),
       write_barriers_invoked_since_last_step_(0),
       idle_marking_delay_counter_(0),
       no_marking_scope_depth_(0),
       unscanned_bytes_of_large_object_(0),
       was_activated_(false),
       black_allocation_(false),
       finalize_marking_completed_(false),
       incremental_marking_finalization_rounds_(0),
-      request_type_(COMPLETE_MARKING) {}
+      request_type_(NONE) {}
 
 bool IncrementalMarking::BaseRecordWrite(HeapObject* obj, Object* value) {
   HeapObject* value_heap_obj = HeapObject::cast(value);
   MarkBit value_bit = Marking::MarkBitFrom(value_heap_obj);
   DCHECK(!Marking::IsImpossible(value_bit));
 
   MarkBit obj_bit = Marking::MarkBitFrom(obj);
   DCHECK(!Marking::IsImpossible(obj_bit));
   bool is_black = Marking::IsBlack(obj_bit);
 
@@ skipping 1234 matching lines @@
 void IncrementalMarking::IncrementIdleMarkingDelayCounter() {
   idle_marking_delay_counter_++;
 }
 
 
 void IncrementalMarking::ClearIdleMarkingDelayCounter() {
   idle_marking_delay_counter_ = 0;
 }
 }  // namespace internal
 }  // namespace v8