Introduce a RandonNumberGenerator class. Refactor the random/private_random uses in Isolate/Context.

test/cctest/test-platform-linux.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 22 matching lines @@
 
 #include "v8.h"
 
 #include "platform.h"
 #include "cctest.h"
 
 using namespace ::v8::internal;
 
 
 TEST(VirtualMemory) {
-  OS::SetUp();
   VirtualMemory* vm = new VirtualMemory(1 * MB);
   CHECK(vm->IsReserved());
   void* block_addr = vm->address();
   size_t block_size = 4 * KB;
   CHECK(vm->Commit(block_addr, block_size, false));
   // Check whether we can write to memory.
   int* addr = static_cast<int*>(block_addr);
   addr[KB-1] = 2;
   CHECK(vm->Uncommit(block_addr, block_size));
   delete vm;
 }
 
 
 TEST(GetCurrentProcessId) {
-  OS::SetUp();
   CHECK_EQ(static_cast<int>(getpid()), OS::GetCurrentProcessId());
 }