Move atomic ops and related files to base library

src/base/once.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "src/once.h"
+#include "src/base/once.h"
 
 #ifdef _WIN32
 #include <windows.h>
 #else
 #include <sched.h>
 #endif
 
-#include "src/atomicops.h"
+#include "src/base/atomicops.h"
 
 namespace v8 {
-namespace internal {
+namespace base {
 
 void CallOnceImpl(OnceType* once, PointerArgFunction init_func, void* arg) {
   AtomicWord state = Acquire_Load(once);
   // Fast path. The provided function was already executed.
   if (state == ONCE_STATE_DONE) {
     return;
   }
 
   // The function execution did not complete yet. The once object can be in one
   // of the two following states:
@@ skipping 16 matching lines @@
 #ifdef _WIN32
       ::Sleep(0);
 #else
       sched_yield();
 #endif
       state = Acquire_Load(once);
     }
   }
 }
 
-} }  // namespace v8::internal
+} }  // namespace v8::base