Remove #pragma once. Just from base/ for now.

base/memory/aligned_memory.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // AlignedMemory is a POD type that gives you a portable way to specify static
 // or local stack data of a given alignment and size. For example, if you need
 // static storage for a class, but you want manual control over when the object
 // is constructed and destructed (you don't want static initialization and
 // destruction), use AlignedMemory:
 //
 //   static AlignedMemory<sizeof(MyClass), ALIGNOF(MyClass)> my_class;
 //
 //   // ... at runtime:
 //   new(my_class.void_data()) MyClass();
 //
 //   // ... use it:
 //   MyClass* mc = my_class.data_as<MyClass>();
 //
 //   // ... later, to destruct my_class:
 //   my_class.data_as<MyClass>()->MyClass::~MyClass();
 
 #ifndef BASE_MEMORY_ALIGNED_MEMORY_H_
 #define BASE_MEMORY_ALIGNED_MEMORY_H_
-#pragma once
 
 #include "base/basictypes.h"
 #include "base/compiler_specific.h"
 #include "base/logging.h"
 
 namespace base {
 
 // AlignedMemory is specialized for all supported alignments.
 // Make sure we get a compiler error if someone uses an unsupported alignment.
 template <size_t Size, size_t ByteAlignment>
@@ skipping 33 matching lines @@
 BASE_DECL_ALIGNED_MEMORY(128);
 BASE_DECL_ALIGNED_MEMORY(256);
 BASE_DECL_ALIGNED_MEMORY(512);
 BASE_DECL_ALIGNED_MEMORY(1024);
 BASE_DECL_ALIGNED_MEMORY(2048);
 BASE_DECL_ALIGNED_MEMORY(4096);
 
 }  // base
 
 #endif  // BASE_MEMORY_ALIGNED_MEMORY_H_