Change SkImageDecoders to take an SkStreamRewindable.

src/images/SkImageDecoder.cpp

Index: src/images/SkImageDecoder.cpp
diff --git a/src/images/SkImageDecoder.cpp b/src/images/SkImageDecoder.cpp
index 7c4c477e078c40fbb584da79590e775a30229775..a9204f1f8bb252441203f89b0ebc47a7d32b4a4a 100644
--- a/src/images/SkImageDecoder.cpp
+++ b/src/images/SkImageDecoder.cpp
@@ -186,7 +186,7 @@ SkBitmap::Config SkImageDecoder::getPrefConfig(SrcDepth srcDepth,
     return config;
 }
 
-bool SkImageDecoder::decode(SkStream* stream, SkBitmap* bm,
+bool SkImageDecoder::decode(SkStreamRewindable* stream, SkBitmap* bm,
                             SkBitmap::Config pref, Mode mode) {
     // we reset this to false before calling onDecode
     fShouldCancelDecode = false;
@@ -213,8 +213,8 @@ bool SkImageDecoder::decodeSubset(SkBitmap* bm, const SkIRect& rect,
     return this->onDecodeSubset(bm, rect);
 }
 
-bool SkImageDecoder::buildTileIndex(SkStream* stream,
-                                int *width, int *height) {
+bool SkImageDecoder::buildTileIndex(SkStreamRewindable* stream,
+                                    int *width, int *height) {
     // we reset this to false before calling onBuildTileIndex
     fShouldCancelDecode = false;
 
@@ -276,7 +276,7 @@ bool SkImageDecoder::DecodeFile(const char file[], SkBitmap* bm,
     SkASSERT(file);
     SkASSERT(bm);
 
-    SkAutoTUnref<SkStream> stream(SkStream::NewFromFile(file));
+    SkAutoTUnref<SkStreamRewindable> stream(SkStream::NewFromFile(file));
     if (stream.get()) {
         if (SkImageDecoder::DecodeStream(stream, bm, pref, mode, format)) {
             bm->pixelRef()->setURI(file);
@@ -337,7 +337,7 @@ private:
  *  @return True if the bounds were decoded and the bitmap is 8888 or can be
  *      copied to 8888.
  */
-static bool decode_bounds_to_8888(SkImageDecoder* decoder, SkStream* stream,
+static bool decode_bounds_to_8888(SkImageDecoder* decoder, SkStreamRewindable* stream,
                                   SkBitmap* bitmap) {
     SkASSERT(decoder != NULL);
     SkASSERT(stream != NULL);
@@ -370,7 +370,7 @@ static bool decode_bounds_to_8888(SkImageDecoder* decoder, SkStream* stream,
  *  @param target Preallocated memory for storing pixels.
  *  @return bool Whether the decode (and copy, if necessary) succeeded.
  */
-static bool decode_pixels_to_8888(SkImageDecoder* decoder, SkStream* stream,
+static bool decode_pixels_to_8888(SkImageDecoder* decoder, SkStreamRewindable* stream,
                                   SkBitmap* bitmap, void* target) {
     SkASSERT(decoder != NULL);
     SkASSERT(stream != NULL);
@@ -445,8 +445,9 @@ bool SkImageDecoder::DecodeMemoryToTarget(const void* buffer, size_t size,
 }
 
 
-bool SkImageDecoder::DecodeStream(SkStream* stream, SkBitmap* bm,
-                          SkBitmap::Config pref, Mode mode, Format* format) {
+bool SkImageDecoder::DecodeStream(SkStreamRewindable* stream, SkBitmap* bm,
+                                  SkBitmap::Config pref, Mode mode,
+                                  Format* format) {
     SkASSERT(stream);
     SkASSERT(bm);