Parallelize cpplint in presubmit and fix usage of DISALLOW_* macros.

src/heap.h

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 2595 matching lines @@
 
   Object* search_target_;
   bool found_target_;
   bool found_target_in_trace_;
   WhatToFind what_to_find_;
   VisitMode visit_mode_;
   List<Object*> object_stack_;
 
   AssertNoAllocation no_alloc;  // i.e. no gc allowed.
 
+ private:
   DISALLOW_IMPLICIT_CONSTRUCTORS(PathTracer);
 };
 #endif  // DEBUG || LIVE_OBJECT_LIST
 
 } }  // namespace v8::internal
 
 #undef HEAP
 
 #endif  // V8_HEAP_H_