Fail to return a codec if the provided stream does not support rewind.

src/images/SkImageDecoder_Factory.cpp

Index: src/images/SkImageDecoder_Factory.cpp
diff --git a/src/images/SkImageDecoder_Factory.cpp b/src/images/SkImageDecoder_Factory.cpp
index 5640e0d9df90d5e53fbbaf01710733edfddf249b..c276a3d4ebe76048eac9b3798afa1360fce464b9 100644
--- a/src/images/SkImageDecoder_Factory.cpp
+++ b/src/images/SkImageDecoder_Factory.cpp
@@ -25,7 +25,16 @@ SkImageDecoder* SkImageDecoder::Factory(SkStream* stream) {
         codec = curr->factory()(stream);
         // we rewind here, because we promise later when we call "decode", that
         // the stream will be at its beginning.
-        stream->rewind();
+        bool rewindSuceeded = stream->rewind();
+
+        // our image decoder's require that rewind is supported so we fail early
+        // if we are given a stream that does not support rewinding.
+        if (!rewindSuceeded) {
+            SkDEBUGF(("Unable to rewind the image stream."));
+            SkDELETE(codec);
+            return NULL;
+        }
+
         if (codec) {
             return codec;
         }