[heap] Unify MarkingDeque push and unshift operations.

test/cctest/test-mark-compact.cc

 // 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 41 matching lines @@
   int mem_size = 20 * kPointerSize;
   byte* mem = NewArray<byte>(20*kPointerSize);
   Address low = reinterpret_cast<Address>(mem);
   Address high = low + mem_size;
   MarkingDeque s;
   s.Initialize(low, high);
 
   Address original_address = reinterpret_cast<Address>(&s);
   Address current_address = original_address;
   while (!s.IsFull()) {
-    s.PushBlack(HeapObject::FromAddress(current_address));
+    s.Push(HeapObject::FromAddress(current_address));
     current_address += kPointerSize;
   }
 
   while (!s.IsEmpty()) {
     Address value = s.Pop()->address();
     current_address -= kPointerSize;
     CHECK_EQ(current_address, value);
   }
 
   CHECK_EQ(original_address, current_address);
@@ skipping 412 matching lines @@
 
 
 TEST(RegressJoinThreadsOnIsolateDeinit) {
   intptr_t size_limit = ShortLivingIsolate() * 2;
   for (int i = 0; i < 10; i++) {
     CHECK_GT(size_limit, ShortLivingIsolate());
   }
 }
 
 #endif  // __linux__ and !USE_SIMULATOR