[heap] Remove unused CompactionMode flag

src/heap/mark-compact.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_HEAP_MARK_COMPACT_H_
 #define V8_HEAP_MARK_COMPACT_H_
 
 #include <deque>
 
 #include "src/base/bits.h"
@@ skipping 413 matching lines @@
 
   void AddEvacuationCandidate(Page* p);
 
   // Prepares for GC by resetting relocation info in old and map spaces and
   // choosing spaces to compact.
   void Prepare();
 
   // Performs a global garbage collection.
   void CollectGarbage();
 
-  enum CompactionMode { INCREMENTAL_COMPACTION, NON_INCREMENTAL_COMPACTION };
-
-  bool StartCompaction(CompactionMode mode);
+  bool StartCompaction();
 
   void AbortCompaction();
 
 #ifdef DEBUG
   // Checks whether performing mark-compact collection.
   bool in_use() { return state_ > PREPARE_GC; }
   bool are_map_pointers_encoded() { return state_ == UPDATE_POINTERS; }
 #endif
 
   // Determine type of object and emit deletion log event.
@@ skipping 327 matching lines @@
 
  private:
   MarkCompactCollector* collector_;
 };
 
 V8_EXPORT_PRIVATE const char* AllocationSpaceName(AllocationSpace space);
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_MARK_COMPACT_H_