Individually enable and disable SkCodecs

tests/YUVTest.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 "SkCodec.h"
 #include "Resources.h"
 #include "SkStream.h"
 #include "SkTemplates.h"
 #include "Test.h"
 
+#ifdef SK_CODEC_DECODES_JPEG
+
 static SkStreamAsset* resource(const char path[]) {
     SkString fullPath = GetResourcePath(path);
     return SkStream::NewFromFile(fullPath.c_str());
 }
 
 static void codec_yuv(skiatest::Reporter* reporter,
                   const char path[],
                   SkISize expectedSizes[3]) {
     SkAutoTDelete<SkStream> stream(resource(path));
     if (!stream) {
@@ skipping 88 matching lines @@
     codec_yuv(r, "brickwork-texture.jpg", sizes);
     codec_yuv(r, "brickwork_normal-map.jpg", sizes);
 
     // A CMYK encoded image should fail.
     codec_yuv(r, "CMYK.jpg", nullptr);
     // A grayscale encoded image should fail.
     codec_yuv(r, "grayscale.jpg", nullptr);
     // A PNG should fail.
     codec_yuv(r, "arrow.png", nullptr);
 }
+
+#endif