Qualify the return value of SkImageDecoder::decode

tests/ImageDecodingTest.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "Resources.h"
 #include "SkBitmap.h"
 #include "SkCanvas.h"
@@ skipping 75 matching lines @@
         return;
     }
 
     SkAutoTDelete<SkImageDecoder> decoder(SkImageDecoder::Factory(&stream));
     if (NULL == decoder.get()) {
         SkDebugf("couldn't decode %s\n", filename.c_str());
         return;
     }
 
     bool success = decoder->decode(&stream, &bm8888, kN32_SkColorType,
-                                   SkImageDecoder::kDecodePixels_Mode);
+                                   SkImageDecoder::kDecodePixels_Mode) != SkImageDecoder::kFailure;
     if (!success) {
         return;
     }
 
     success = stream.rewind();
     REPORTER_ASSERT(reporter, success);
     if (!success) {
         return;
     }
 
     decoder->setRequireUnpremultipliedColors(true);
     success = decoder->decode(&stream, &bm8888Unpremul, kN32_SkColorType,
-                              SkImageDecoder::kDecodePixels_Mode);
+                              SkImageDecoder::kDecodePixels_Mode) != SkImageDecoder::kFailure;
     if (!success) {
         return;
     }
 
     bool dimensionsMatch = bm8888.width() == bm8888Unpremul.width()
                            && bm8888.height() == bm8888Unpremul.height();
     REPORTER_ASSERT(reporter, dimensionsMatch);
     if (!dimensionsMatch) {
         return;
     }
@@ skipping 685 matching lines @@
 
     pixels[pixelCount] = sentinal;  // This value should not be changed.
 
     SkAutoTUnref<SingleAllocator> allocator(
             SkNEW_ARGS(SingleAllocator,
                        ((void*)pixels.get(), sizeof(uint16_t) * pixelCount)));
     decoder->setAllocator(allocator);
     decoder->setSampleSize(2);
     SkBitmap bitmap;
     bool success = decoder->decode(stream, &bitmap, kRGB_565_SkColorType,
-                                   SkImageDecoder::kDecodePixels_Mode);
+                                   SkImageDecoder::kDecodePixels_Mode) != SkImageDecoder::kFailure;
     REPORTER_ASSERT(r, success);
     REPORTER_ASSERT(r, !allocator->ready());  // Decoder used correct memory
     REPORTER_ASSERT(r, sentinal == pixels[pixelCount]);
 }