Revert "Remove FX_Alloc() null checks now that it can't return NULL."

core/src/fxcodec/codec/fx_codec_jpx_opj.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 <algorithm>
 #include <limits>
 
 #include "../../../include/fxcodec/fx_codec.h"
@@ skipping 697 matching lines @@
     FX_LPBYTE pChannel, pScanline, pPixel;
 
     if(image->comps[0].w != image->x1 || image->comps[0].h != image->y1) {
         return FALSE;
     }
     if(pitch < (int)(image->comps[0].w * 8 * image->numcomps + 31) >> 5 << 2) {
         return FALSE;
     }
     FXSYS_memset8(dest_buf, 0xff, image->y1 * pitch);
     FX_BYTE** channel_bufs = FX_Alloc(FX_BYTE*, image->numcomps);
+    if (channel_bufs == NULL) {
+        return FALSE;
+    }
     FX_BOOL result = FALSE;
     int* adjust_comps = FX_Alloc(int, image->numcomps);
+    if (adjust_comps == NULL) {
+        goto done;
+    }
     for (i = 0; i < (int)image->numcomps; i ++) {
         channel_bufs[i] = dest_buf + offsets[i];
         adjust_comps[i] = image->comps[i].prec - 8;
         if(i > 0) {
             if(image->comps[i].dx != image->comps[i - 1].dx
                     || image->comps[i].dy != image->comps[i - 1].dy
                     || image->comps[i].prec != image->comps[i - 1].prec) {
                 goto done;
             }
         }
@@ skipping 73 matching lines @@
 FX_BOOL CCodec_JpxModule::Decode(void* ctx, FX_LPBYTE dest_data, int pitch, FX_BOOL bTranslateColor, FX_LPBYTE offsets)
 {
     CJPX_Decoder* pDecoder = (CJPX_Decoder*)ctx;
     return pDecoder->Decode(dest_data, pitch, bTranslateColor, offsets);
 }
 void CCodec_JpxModule::DestroyDecoder(void* ctx)
 {
     CJPX_Decoder* pDecoder = (CJPX_Decoder*)ctx;
     delete pDecoder;
 }