Change SkImageDecoders to take an SkStreamRewindable.

src/images/SkImageRef.cpp

Index: src/images/SkImageRef.cpp
diff --git a/src/images/SkImageRef.cpp b/src/images/SkImageRef.cpp
index bd4a7393d9fc9a3a029ca6ee5d053ef2938571cf..9093b0515662d24dda6023d4dedf00575a1e69a2 100644
--- a/src/images/SkImageRef.cpp
+++ b/src/images/SkImageRef.cpp
@@ -18,7 +18,7 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-SkImageRef::SkImageRef(SkStream* stream, SkBitmap::Config config,
+SkImageRef::SkImageRef(SkStreamRewindable* stream, SkBitmap::Config config,
                        int sampleSize, SkBaseMutex* mutex)
         : SkPixelRef(mutex), fErrorInDecoding(false) {
     SkASSERT(stream);
@@ -79,7 +79,7 @@ SkImageDecoderFactory* SkImageRef::setDecoderFactory(
 
 ///////////////////////////////////////////////////////////////////////////////
 
-bool SkImageRef::onDecode(SkImageDecoder* codec, SkStream* stream,
+bool SkImageRef::onDecode(SkImageDecoder* codec, SkStreamRewindable* stream,
                           SkBitmap* bitmap, SkBitmap::Config config,
                           SkImageDecoder::Mode mode) {
     return codec->decode(stream, bitmap, config, mode);