Move platform abstraction to base library

src/incremental-marking.h

 // 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.
 
 #ifndef V8_INCREMENTAL_MARKING_H_
 #define V8_INCREMENTAL_MARKING_H_
 
 
 #include "src/execution.h"
 #include "src/mark-compact.h"
@@ skipping 213 matching lines @@
 
   INLINE(void ProcessMarkingDeque(intptr_t bytes_to_process));
 
   INLINE(void VisitObject(Map* map, HeapObject* obj, int size));
 
   Heap* heap_;
 
   State state_;
   bool is_compacting_;
 
-  VirtualMemory* marking_deque_memory_;
+  base::VirtualMemory* marking_deque_memory_;
   bool marking_deque_memory_committed_;
   MarkingDeque marking_deque_;
 
   int steps_count_;
   double steps_took_;
   double longest_step_;
   int64_t old_generation_space_available_at_start_of_incremental_;
   int64_t old_generation_space_used_at_start_of_incremental_;
   int steps_count_since_last_gc_;
   double steps_took_since_last_gc_;
   int64_t bytes_rescanned_;
   bool should_hurry_;
   int marking_speed_;
   intptr_t bytes_scanned_;
   intptr_t allocated_;
   intptr_t write_barriers_invoked_since_last_step_;
 
   int no_marking_scope_depth_;
 
   int unscanned_bytes_of_large_object_;
 
   DISALLOW_IMPLICIT_CONSTRUCTORS(IncrementalMarking);
 };
 
 } }  // namespace v8::internal
 
 #endif  // V8_INCREMENTAL_MARKING_H_