Option for SkCodec to treat dst as all zeroes.

src/core/SkImageGenerator.cpp

 /*
  * Copyright 2014 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkImageGenerator.h"
 
 bool SkImageGenerator::getInfo(SkImageInfo* info) {
     SkImageInfo dummy;
     if (NULL == info) {
         info = &dummy;
     }
     return this->onGetInfo(info);
 }
 
 SkImageGenerator::Result SkImageGenerator::getPixels(const SkImageInfo& info, void* pixels,
-                                                     size_t rowBytes, SkPMColor ctable[],
-                                                     int* ctableCount) {
+                                                     size_t rowBytes, const Options* options,
+                                                     SkPMColor ctable[], int* ctableCount) {
     if (kUnknown_SkColorType == info.colorType()) {
         return kInvalidConversion;
     }
     if (NULL == pixels) {
         return kInvalidParameters;
     }
     if (rowBytes < info.minRowBytes()) {
         return kInvalidParameters;
     }
 
     if (kIndex_8_SkColorType == info.colorType()) {
         if (NULL == ctable || NULL == ctableCount) {
             return kInvalidParameters;
         }
     } else {
         if (ctableCount) {
             *ctableCount = 0;
         }
         ctableCount = NULL;
         ctable = NULL;
     }
 
-    const Result result = this->onGetPixels(info, pixels, rowBytes, ctable, ctableCount);
+    // Default options.
+    Options optsStorage;
+    if (NULL == options) {
+        options = &optsStorage;
+    }
+    const Result result = this->onGetPixels(info, pixels, rowBytes, *options, ctable, ctableCount);
 
     if ((kIncompleteInput == result || kSuccess == result) && ctableCount) {
         SkASSERT(*ctableCount >= 0 && *ctableCount <= 256);
     }
     return result;
 }
 
 SkImageGenerator::Result SkImageGenerator::getPixels(const SkImageInfo& info, void* pixels,
                                                      size_t rowBytes) {
     SkASSERT(kIndex_8_SkColorType != info.colorType());
     if (kIndex_8_SkColorType == info.colorType()) {
         return kInvalidConversion;
     }
-    return this->getPixels(info, pixels, rowBytes, NULL, NULL);
+    return this->getPixels(info, pixels, rowBytes, NULL, NULL, NULL);
 }
 
 bool SkImageGenerator::getYUV8Planes(SkISize sizes[3], void* planes[3], size_t rowBytes[3],
                                      SkYUVColorSpace* colorSpace) {
 #ifdef SK_DEBUG
     // In all cases, we need the sizes array
     SkASSERT(sizes);
 
     bool isValidWithPlanes = (planes) && (rowBytes) &&
         ((planes[0]) && (planes[1]) && (planes[2]) &&
@@ skipping 44 matching lines @@
 /////////////////////////////////////////////////////////////////////////////////////////////
 
 SkData* SkImageGenerator::onRefEncodedData() {
     return NULL;
 }
 
 bool SkImageGenerator::onGetInfo(SkImageInfo*) {
     return false;
 }
 
+#ifdef SK_SUPPORT_LEGACY_OPTIONLESS_GET_PIXELS
 SkImageGenerator::Result SkImageGenerator::onGetPixels(const SkImageInfo&, void*, size_t,
                                                        SkPMColor*, int*) {
     return kUnimplemented;
 }
+#endif
+
+SkImageGenerator::Result SkImageGenerator::onGetPixels(const SkImageInfo& info, void* dst,
+                                                       size_t rb, const Options& options,
+                                                       SkPMColor* colors, int* colorCount) {
+#ifdef SK_SUPPORT_LEGACY_OPTIONLESS_GET_PIXELS
+    return this->onGetPixels(info, dst, rb, colors, colorCount);
+#else
+    return kUnimplemented;
+#endif
+}