Revert of skstd -> std for unique_ptr

src/android/SkBitmapRegionDecoder.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmapRegionCanvas.h"
 #include "SkBitmapRegionCodec.h"
 #include "SkBitmapRegionDecoder.h"
@@ skipping 31 matching lines @@
                     break;
                 default:
                     SkCodecPrintf("Error: Scanline ordering not supported.\n");
                     return nullptr;
             }
             return new SkBitmapRegionCanvas(codec.detach());
         }
         case kAndroidCodec_Strategy: {
             SkAutoTDelete<SkAndroidCodec> codec =
                     SkAndroidCodec::NewFromStream(streamDeleter.detach());
-            if (!codec) {
+            if (NULL == codec) {
                 SkCodecPrintf("Error: Failed to create codec.\n");
-                return nullptr;
+                return NULL;
             }
             return new SkBitmapRegionCodec(codec.detach());
         }
         default:
             SkASSERT(false);
             return nullptr;
     }
 }