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

src/platform-cygwin.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 218 matching lines @@
     // Use a multiple of 64k to prevent committing unused memory.
     // Note: This does not guarantee RWX regions will be within the
     // range kAllocationRandomAddressMin to kAllocationRandomAddressMax
 #ifdef V8_HOST_ARCH_64_BIT
     static const intptr_t kAllocationRandomAddressMin = 0x0000000080000000;
     static const intptr_t kAllocationRandomAddressMax = 0x000003FFFFFF0000;
 #else
     static const intptr_t kAllocationRandomAddressMin = 0x04000000;
     static const intptr_t kAllocationRandomAddressMax = 0x3FFF0000;
 #endif
-    uintptr_t address = (V8::RandomPrivate(isolate) << kPageSizeBits)
-        | kAllocationRandomAddressMin;
+    uintptr_t address =
+        (isolate->random_number_generator()->NextInt() << kPageSizeBits) |
+        kAllocationRandomAddressMin;
     address &= kAllocationRandomAddressMax;
     return reinterpret_cast<void *>(address);
   }
   return NULL;
 }
 
 
 static void* RandomizedVirtualAlloc(size_t size, int action, int protection) {
   LPVOID base = NULL;
 
@@ skipping 108 matching lines @@
 bool VirtualMemory::ReleaseRegion(void* base, size_t size) {
   return VirtualFree(base, 0, MEM_RELEASE) != 0;
 }
 
 
 bool VirtualMemory::HasLazyCommits() {
   // TODO(alph): implement for the platform.
   return false;
 }
 
-
-void OS::SetUp() {
-  // Seed the random number generator.
-  // Convert the current time to a 64-bit integer first, before converting it
-  // to an unsigned. Going directly can cause an overflow and the seed to be
-  // set to all ones. The seed will be identical for different instances that
-  // call this setup code within the same millisecond.
-  uint64_t seed = static_cast<uint64_t>(TimeCurrentMillis());
-  srandom(static_cast<unsigned int>(seed));
-}
-
-
 } }  // namespace v8::internal