Allow ico decoder to decode PNG sub-images.

src/images/SkImageDecoder.cpp

 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkImageDecoder.h"
 #include "SkBitmap.h"
@@ skipping 32 matching lines @@
     , fPreferQualityOverSpeed(false)
     , fRequireUnpremultipliedColors(false) {
 }
 
 SkImageDecoder::~SkImageDecoder() {
     SkSafeUnref(fPeeker);
     SkSafeUnref(fChooser);
     SkSafeUnref(fAllocator);
 }
 
+void SkImageDecoder::copyFieldsToOther(SkImageDecoder* other) {
+    if (NULL == other) {
+        return;
+    }
+    other->setPeeker(fPeeker);
+    other->setChooser(fChooser);
+    other->setAllocator(fAllocator);
+    other->setSampleSize(fSampleSize);
+    if (fUsePrefTable) {
+        other->setPrefConfigTable(fPrefTable);
+    } else {
+        other->fDefaultPref = fDefaultPref;
+    }
+    other->setPreferQualityOverSpeed(fPreferQualityOverSpeed);
+    other->setRequireUnpremultipliedColors(fRequireUnpremultipliedColors);
+}
+
 SkImageDecoder::Format SkImageDecoder::getFormat() const {
     return kUnknown_Format;
 }
 
 const char* SkImageDecoder::getFormatName() const {
     return GetFormatName(this->getFormat());
 }
 
 const char* SkImageDecoder::GetFormatName(Format format) {
     switch (format) {
@@ skipping 381 matching lines @@
             if (kUnknown_Format == *format) {
                 if (stream->rewind()) {
                     *format = GetStreamFormat(stream);
                 }
             }
         }
         delete codec;
     }
     return success;
 }