Change SkImageDecoders to take an SkStreamRewindable.

tests/ImageDecodingTest.cpp

Index: tests/ImageDecodingTest.cpp
diff --git a/tests/ImageDecodingTest.cpp b/tests/ImageDecodingTest.cpp
index afab02f7a57fe434bae14f9dcd11cbed7fea1a61..59afb07d52588b8803bc13eed5111603557f21f2 100644
--- a/tests/ImageDecodingTest.cpp
+++ b/tests/ImageDecodingTest.cpp
@@ -163,7 +163,7 @@ public:
     }
 
 protected:
-    virtual bool onDecode(SkStream*, SkBitmap* bitmap, Mode) SK_OVERRIDE {
+    virtual bool onDecode(SkStreamRewindable*, SkBitmap* bitmap, Mode) SK_OVERRIDE {
         return false;
     }
 };
@@ -194,7 +194,7 @@ static void test_unpremul(skiatest::Reporter* reporter) {
 
 #ifdef SK_DEBUG
 // Create a stream containing a bitmap encoded to Type type.
-static SkStream* create_image_stream(SkImageEncoder::Type type) {
+static SkMemoryStream* create_image_stream(SkImageEncoder::Type type) {
     SkBitmap bm;
     const int size = 50;
     bm.setConfig(SkBitmap::kARGB_8888_Config, size, size);
@@ -233,7 +233,7 @@ static void test_stream_life() {
     };
     for (size_t i = 0; i < SK_ARRAY_COUNT(gTypes); ++i) {
         SkDebugf("encoding to %i\n", i);
-        SkAutoTUnref<SkStream> stream(create_image_stream(gTypes[i]));
+        SkAutoTUnref<SkMemoryStream> stream(create_image_stream(gTypes[i]));
         if (NULL == stream.get()) {
             SkDebugf("no stream\n");
             continue;