Add NewFromStream and getEncodedFormat to BitmapRegionDecoder

tools/SkBitmapRegionDecoderInterface.h

Index: tools/SkBitmapRegionDecoderInterface.h
diff --git a/tools/SkBitmapRegionDecoderInterface.h b/tools/SkBitmapRegionDecoderInterface.h
index a6a31114578e7c70c86ce2f70dfe635cb6808d62..8e19e95a0a9867557dce940725d6b714e46627e8 100644
--- a/tools/SkBitmapRegionDecoderInterface.h
+++ b/tools/SkBitmapRegionDecoderInterface.h
@@ -9,6 +9,7 @@
 #define SkBitmapRegionDecoder_DEFINED
 
 #include "SkBitmap.h"
+#include "SkEncodedFormat.h"
 #include "SkStream.h"
 
 /*
@@ -33,6 +34,14 @@ public:
             SkData* data, Strategy strategy);
 
     /*
+     * @param stream   Takes ownership of the stream
+     * @param strategy Strategy used for scaling and subsetting
+     * @return         Tries to create an SkBitmapRegionDecoder, returns NULL on failure
+     */
+    static SkBitmapRegionDecoderInterface* CreateBitmapRegionDecoder(
+            SkStreamRewindable* stream, Strategy strategy);
+
+    /*
      * Decode a scaled region of the encoded image stream
      *
      * @param bitmap          Container for decoded pixels.  It is assumed that the pixels
@@ -59,6 +68,8 @@ public:
      */
     virtual bool conversionSupported(SkColorType colorType) = 0;
 
+    virtual SkEncodedFormat getEncodedFormat() = 0;
+
     int width() const { return fWidth; }
     int height() const { return fHeight; }