Align base::Pickle allocations to 4k boundaries

base/bits.h

 // Copyright (c) 2009 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.
 
 // This file defines some bit utilities.
 
 #ifndef BASE_BITS_H_
 #define BASE_BITS_H_
 
 #include "base/basictypes.h"
@@ skipping 23 matching lines @@
 // Returns the integer i such as 2^(i-1) < n <= 2^i
 inline int Log2Ceiling(uint32 n) {
   if (n == 0) {
     return -1;
   } else {
     // Log2Floor returns -1 for 0, so the following works correctly for n=1.
     return 1 + Log2Floor(n - 1);
   }
 }
 
+// Round up |size| to a multiple of alignment, which must be a power of two.
+inline size_t Align(size_t size, size_t alignment) {
+  DCHECK_EQ(alignment & (alignment - 1), 0u);
+  return (size + alignment - 1) & ~(alignment - 1);
+}
+
 }  // namespace bits
 }  // namespace base
 
 #endif  // BASE_BITS_H_