Merge to XFA: Remove FX_Alloc() null checks now that it can't return NULL.

core/src/fxcrt/fx_basic_plex.cpp

 // 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
 
 #include "../../include/fxcrt/fx_basic.h"
 #include "plex.h"
 CFX_Plex* CFX_Plex::Create(CFX_Plex*& pHead, FX_DWORD nMax, FX_DWORD cbElement)
 {
     CFX_Plex* p = (CFX_Plex*)FX_Alloc(FX_BYTE, sizeof(CFX_Plex) + nMax * cbElement);
-    if (!p) {
-        return NULL;
-    }
     p->pNext = pHead;
     pHead = p;
     return p;
 }
 void CFX_Plex::FreeDataChain()
 {
     CFX_Plex* p = this;
     while (p != NULL) {
         FX_BYTE* bytes = (FX_BYTE*)p;
         CFX_Plex* pNext = p->pNext;
         FX_Free(bytes);
         p = pNext;
     }
 }