Sort includes in xfa/.

core/include/fxcrt/fx_memory.h

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #ifndef CORE_INCLUDE_FXCRT_FX_MEMORY_H_
 #define CORE_INCLUDE_FXCRT_FX_MEMORY_H_
 
 #include "core/include/fxcrt/fx_system.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
+
 // For external C libraries to malloc through PDFium. These may return NULL.
 void* FXMEM_DefaultAlloc(size_t byte_size, int flags);
 void* FXMEM_DefaultRealloc(void* pointer, size_t new_size, int flags);
 void FXMEM_DefaultFree(void* pointer, int flags);
+
 #ifdef __cplusplus
 }  // extern "C"
 
 #include <stdlib.h>
 #include <limits>
 #include <new>
 
 NEVER_INLINE void FX_OutOfMemoryTerminate();
 
 inline void* FX_SafeRealloc(void* ptr, size_t num_members, size_t member_size) {
@@ skipping 72 matching lines @@
   void FreeAll();
 
  private:
   size_t m_TrunkSize;
 
   void* m_pFirstTrunk;
 };
 #endif  // __cplusplus
 
 #endif  // CORE_INCLUDE_FXCRT_FX_MEMORY_H_