Valgrind cleanliness, part 6: Introduce OS::TearDown, cleaning up 2 mutexes.

src/platform-nullos.cc

 // Copyright 2006-2008 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 73 matching lines @@
   // Seed the random number generator.
   UNIMPLEMENTED();
 }
 
 
 void OS::PostSetUp() {
   UNIMPLEMENTED();
 }
 
 
+void OS::TearDown() {
+  UNIMPLEMENTED();
+}
+
+
 // Returns the accumulated user time for thread.
 int OS::GetUserTime(uint32_t* secs,  uint32_t* usecs) {
   UNIMPLEMENTED();
   *secs = 0;
   *usecs = 0;
   return 0;
 }
 
 
 // Returns current time as the number of milliseconds since
@@ skipping 388 matching lines @@
   UNIMPLEMENTED();
 }
 
 
 void ProfileSampler::Stop() {
   UNIMPLEMENTED();
 }
 
 
 } }  // namespace v8::internal