Simplify implementation of Mutex.

src/spaces.cc

 // Copyright 2011 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 2025 matching lines @@
 }
 
 
 intptr_t FreeListCategory::Concatenate(FreeListCategory* category) {
   intptr_t free_bytes = 0;
   if (category->top_ != NULL) {
     ASSERT(category->end_ != NULL);
     // This is safe (not going to deadlock) since Concatenate operations
     // are never performed on the same free lists at the same time in
     // reverse order.
-    ScopedLock lock_target(mutex_);
+    ScopedLock lock_target(mutex());
     ScopedLock lock_source(category->mutex());
     free_bytes = category->available();
     if (end_ == NULL) {
       end_ = category->end();
     } else {
       category->end()->set_next(top_);
     }
     top_ = category->top();
     available_ += category->available();
     category->Reset();
@@ skipping 1152 matching lines @@
     object->ShortPrint();
     PrintF("\n");
   }
   printf(" --------------------------------------\n");
   printf(" Marked: %x, LiveCount: %x\n", mark_size, LiveBytes());
 }
 
 #endif  // DEBUG
 
 } }  // namespace v8::internal